Fifty-six individuals (55%) received their highest loading on the first personality prototype, 35 (34%) on the second, and 11 (10%) on the third. The three factors explained 65% (Factor 1 = 41%, Factor 2 = 17%, and Factor 3 = 7%) of the total variance in the CCQ evaluations. This factor solution is comparable to the one reported for German children by Asendorpf and van Aken (1999). Consistent with our results, these authors also reported that the factors did not differ for the sexes.2 To ensure that the participants were sufficiently pure representatives of only one personality prototype, they had to load at least .40 on one personality prototype and their second highest loading had to be at least .20 lower than their highest loading. Participants with loadings of .40   higher on more than one prototype were excluded. These criteria successfully classified 83 (39 boys and 44 girls) of the 102 participants, or 84%. Subsequent analyses are based on these 83 participants. To ensure that the three personality prototypes were sufficiently different, the participants were assigned to nonoverlapping groups based on their highest loading (see York & John, 1992). The means and standard deviations of the loadings for each factor were then calculated. As Table 1 shows, the mean factor loadings were substantially higher and the mean standard deviations were substantially lower when the participants were assigned to the prototype on which they had received their highest loading.
Interpreting the Psychological Nature of the Three Personality Prototypes The correlations of the personality prototypes with ego resiliency were .79, .33, and –.33; their correlations with ego undercontrol were –.29, .89, and –.11. A multivariate analysis of variance (MANOVA) showed a significant interaction between the three personality prototypes and the two personality constructs (F = 38.03, p < .001), indicating that the three factors were defined by distinctly different configurations of ego resiliency and ego undercontrol. The three personality prototypes were labeled overcontrolled resilients, resilient undercontrollers, and brittles, respectively. To further evaluate the potential effects of attrition, personality prototypes were developed using all 157 children in the age-4 sample, not only the 102 participating in the current study. Also in this larger sample, three replicable prototypes were discerned. The correlations between these prototypes, based on the partly overlapping samples, were also very high, ranging from .99 to .96. The correlations with the ego resiliency and ego undercontrol measures were also virtually identical for the two sets of prototypes. The 10 most and least characteristic CCQ items are displayed in Table 2 separately for each personality prototype. The first personality prototype, overcontrolled resilient, was characterized by CCQ items such as dependable, attentive, helpful, reasonable, and personable, and not by items indicative of aggression, unworthiness, or stress reactivity. This personality configuration portrays a socially well-adjusted preschooler likely to adapt well to a broad range of situations. Block and Block (1980) noted, “For the overcontrolling child, the presence of ego resiliency results in a high degree of socialization that fits and feels well, a relative absence of anxiety and intimidation in reacting to and acting on the world” (p. 88).

The second personality prototype, resilient undercontrol, was characterized by CCQ items such as energetic, assertive, aggressive, expressive, sociable, and able to stand up for themselves. This personality prototype portrays a lively, assertive, and socially outgoing preschooler who is unlikely to withhold his or her thoughts and emotions from others. Consistent with the finding reported by Hart et al. (1997), our undercontrolled factor did not include the elements of interpersonal exploitation reported by Robins et al. (1996) for their undercontrolled type. Robins et al. (1998) subsequently distinguished between two subtypes: the antisocial and the impulsive undercontroller. The resilient undercontroller, largely free of antisocial and interpersonally antagonistic tendencies, appears similar to the impulsive type. The relatively high level of resiliency may explain this absence of undercontrol-related problems. Finally, the third personality prototype, brittles, was characterized by CCQ items such as shyness, hypersensitivity, and anxiety, and not by items indicative of a calm, empathic, and self-reliant mode of relating to others. Replicability of the Personality Prototypes Across Studies Next, we compared our three preschool personality prototypes with the typologies identified by Asendorpf and van Aken (1999), Hart et al. (1997), and Robins et al. (1996).3 To obtain a reliable estimate and to reduce the influence of sample fluctuations, we averaged, separately for each type, the person factor scores obtained in
these three other studies and then correlated the resulting three mean person factor scores with our three personality prototype scores. The resulting convergence correlations were .81 for the first, .71 for the second, and .53 for the third personality prototype. The declining size of the convergence correlations is consistent with previous studies; the highest correlation has always been obtained for the first factor and the lowest correlation has always been obtained for the third factor. This decline in size may result from the lower reliability and poorer definition that can be expected to characterize
later extracted factors (e.g., Hart et al., 1997). In sum, good convergence was found with other studies, although our first factor was slightly more overcontrolled, our second factor slightly more resilient, and our third factor slightly less overcontrolled than the factors reported by Asendorpf and van Aken (1999), Hart et al. (1997), and Robins et al. (1996).
SUMMARY
Consistent with previous studies that used inverse factor analysis to derive personality typologies, this study also identified three preschool personality prototypes. Strong to moderate replicability was obtained. This study provides further evidence for the existence of three reasonably similar personality (proto)types, the nature of which transcends age and national origin.4 The types identified by Robins et al. (1996) in 13-yearsolds may be present in some form already in preschool. Part 2: The Construct Validity of the Preschool Personality Prototypes: Testing Directional Hypotheses Using Laboratory Test Data
The three personality prototypes were characterized by various configurations of ego resiliency and ego undercontrol. This configurality may reduce the correlations between the prototypes and procedures developed to represent relatively pure indices of each ego construct. For example, although children typifying the resilient undercontrolled personality prototype should, theoretically, show low impulse control on ego undercontrol tasks, the degree of undercontrolled behavior might be tempered by their level of ego resiliency. Nonetheless, each personality prototype is largely defined by one ego construct and predictions were therefore made on the basis of this dominant ego component. Given that ego resiliency and IQ overlap conceptually (Block&Kremen, 1996), predictions also were advanced for IQ. Thus, children typifying the overcontrolled resilient personality prototype were expected to perform well on ego resiliency and IQ measures but show no (or only moderate) relations to ego undercontrol procedures, children typifying the resilient undercontrolled personality prototype were expected to score high on ego undercontrol procedures and show no (or only moderate) relations to ego resiliency or IQ measures, and children typifying the brittle personality prototype were expected to perform poorly on ego resiliency and IQ measures. Table 3 presents the correlations between the participants’ loadings on the three personality prototypes and the measures of ego resiliency, ego undercontrol, and IQ.

THE OVERCONTROLLED RESILIENT
PERSONALITY PROTOTYPE
As anticipated, this personality prototype correlated positively (p < .05, or beyond, two-tailed) with the motor inhibition, Lowenfeld mosaics, and IQ procedures. Although the correlation with egocentrism was in the anticipated direction, it was not significant. The negative correlation with the inability to delay gratification task was not expected, but the direction of this correlation was consistent

THE RESILIENT UNDERCONTROLLED
PERSONALITY PROTOTYPE
As anticipated, this personality prototype correlated positively (p < .05, or beyond, two-tailed) with the actometer task but the correlation with inability to delay gratification, although positive, was not significant. As expected, this prototype was unrelated to measures of ego resiliency and intelligence.

THE BRITTLE PERSONALITY PROTOTYPE
As anticipated, this personality prototype correlated negatively (p < .05, or beyond, two-tailed) with the egocentrism, Lowenfeld mosaics, and IQ procedures.
Against predictions, it correlated negatively with the actometer task.

SUMMARY
Relations between the three personality prototypes— based on observer data—and the laboratory procedures indexing resiliency, undercontrol, and IQ showed substantial but not perfect convergence. A directional prediction (r = – or +) was developed for 10 of the 18 possible relations. Of these 10 relations, 7 were statistically significant (p < .05, or beyond) and in the predicted direction. For 8 of the 18 relations, a nonsignificant correlation was
expected. Of these 8 relations, only 2 achieved statistical significance: The overcontrolled resilient prototype correlated negatively with the inability to delay gratification task and the brittle prototype correlated negatively with the actometer task.

Part 3: Developmental Implications of Preschool Personality Prototypes for Adjustment in Adolescence The participants typifying the overcontrolled resilient
personality prototype were anticipated to remain intelligent and overcontrolling in adolescence. They also were expected to be less resilient in adolescence
than in preschool, mainly because the overcontrolling component of this personality prototype was hypothesized to reduce their ability to cope with adolescent challenges (Block&Gjerde, 1986). Undercontrol of impulse has been found to remain relatively longitudinally consistent (Block & Gjerde, 1986; Caspi et al., 1995). The participants typifying the resilient undercontrolled prototype were therefore expected to remain undercontrolled in adolescence. Finally, participants typifying the brittle personality prototype were expected to remain maladjusted and relatively unintelligent; their lack of resiliency was anticipated to minimize their ability to cope with the challenges that characterize adolescence. To determine the relations between preschool personality prototypes and adolescent adjustment, correlations were computed between the personality prototype loadings and (a) the 100 age-14 CAQ items, (b) the personality constructs, (c) the age-11 and age-18 IQ, and (d) the age-14 drug use measure. The number of sex differences in the correlation patterns did not exceed the number to be expected by chance. We therefore only report results for the total sample.

The overcontrolled resilient prototype was significantly associated (p < .05 or beyond) with 33 CAQ items, the resilient undercontrolled prototype with 34 CAQ items, and the brittle prototype with 6 CAQ items.5 The significant items were grouped using principal component analysis. The resulting components were not introduced as replicable factors but only to aid the reader in assimilating the findings; the aim is data reduction not “dimensional discovery” (Lykken, 1971). In principal component analysis, the components are merely linear combinations of the observed variance; thus, underlying hypothetical factors should not be postulated.We therefore refer to the CAQ item correlates of each prototype grouped by means of principal component analysis as “themes,” not as “factors.” The CAQ-based personality themes rendered a psychologically coherent portrait of the first two personality prototypes. Table 4 presents the
relations between the three personality prototypes and the personality constructs, IQ, and drug use.

LONGITUDINAL PERSONALITY CORRELATES OF THE OVERCONTROLLED RESILIENT PROTOTYPE
Three CAQ themes, reclusiveness (16 items, α = .95), introspective acquiescence (7 items, α = .92), and dependable resourcefulness (10 items, α = .85), summarized the CAQ correlates of the overcontrolled resilient prototype. Reclusiveness was positively defined by such observer assessments as “is emotionally bland,” “communicates through action,” and “tends to ruminate” and negatively defined by such CAQ items as “is a talkative individual,” “initiates humor,” and “is facially, gesturally expressive.” Introspective acquiescence was positively defined by such observer assessments as “overcontrols needs, impulses,” “introspective, concerned with self as an object,” and “has readiness to feel guilt” and negatively defined by such CAQ items as “is assertive” and
“tends to proffer advice.” Dependable resourcefulness was positively defined by such observer assessments as “has high degree of intellectual capacity,” “favors conservative values,” and “is calm, relaxed in manner” and negatively defined by such items as “unable to delay gratification,” “tries to stretch limits,” and “is self-indulgent.” The more the participants fit the overcontrolled resilient personality prototype as preschoolers, the more likely they were, as adolescents, to be shy and conscientious and less likely they were to be undercontrolling, active, and extraverted. The correlations with age-11 and age-18 IQ were positive, whereas the correlation with drug use was negative and marginally significant. Summary of the overcontrolled resilient personality prototype. The adolescent attributes associated with this prototype portrayed a relatively well-adapted yet emotionally bland and socially reclusive youth characterized by little overt psychological conflict. These adolescents were solitary, conscientious, and cautious; they were not vivacious or socially at ease. They were nonetheless resourceful, intelligent, and receptive to their own feelings. There was some evidence that their bland social stimulus value concealed access to a differentiated inner life. Why the absence of ego resiliency in the adolescents who typified this preschool personality prototype?
Overcontrolled resilience may have served the participants well in the relatively predictable niches of early childhood. Yet, the overcontrolling component may have reduced their ability to cope resourcefully with the challenges and emotional turbulence during the transition from childhood into adolescence. Second, due to their behavioral inhibition in preschool, the individuals typifying this prototype may have gradually withdrawn from social participation. Their reclusiveness may have limited their opportunity to learn new coping skills relevant to the adolescent adaptation, leading to a decline in their level of resiliency. This pattern exemplifies proactive interaction, whereby individuals select or create their own environments (Caspi&Bem, 1990). Third, the
nursery school teachers also may have overestimated the level of resiliency of these children because of their dependability, helpfulness, and compliance. This pattern may be less advantageous later in life (see also Asendorpf & van Aken, 1999; Gjerde, 1995). Although we are not able to decide among these explanations, undercontrol showed, as anticipated, greater longitudinal consistency than resiliency.

LONGITUDINAL PERSONALITY CORRELATES OF THE RESILIENT UNDERCONTROLLED
PERSONALITY PROTOTYPE
The CAQ correlates of the resilient undercontrolled personality prototype were summarized by three CAQ themes: sociability (15 items, α = .95), assertive independence (10 items, α = .92), and inability to delay gratification (9 items, α = .91). Sociability was positively defined by such observer assessments as “skilled in social techniques,” “initiates humor,” and “is self-dramatizing, histrionic” and negatively defined by such CAQ items as “does not vary roles,” “is emotionally bland,” and “uncomfortable with uncertainty.” Assertive independence was positively defined by such observer assessments as “is assertive,” “tends to proffer advice,” and “values independence, autonomy” and negatively defined by such CAQ items as “submissive, accepts domination,” “has a readiness to feel guilt,” and “vulnerable to threat.” Inability to delay gratification was positively defined by such observer assessments as “unable to delay gratification,” “tries to stretch limits,” and “tends to be rebellious, nonconforming” and negatively defined by such CAQ items as “overcontrols needs, impulses,” “favors conservative values,” and “dependable, responsible person.” The more the participants fit the resilient undercontrolled personality prototype as preschoolers, the more likely they were, as adolescents, to be undercontrolled, active, and extraverted and less likely they were to be shy and conscientious. The correlations with age-11 and age-18 IQ were insignificant, whereas the correlation with drug use was moderately positive.

Summary of the resilient undercontrolled personality prototype. The adolescent attributes associated with this prototype indicated continuation of low impulse control. As adolescents, individuals typifying this personality prototype were sociable, assertive, extraverted, and somewhat lacking in conscientiousness. This pattern resembles the lack of control type (Caspi et al., 1995). Ego undercontrol also may have temperamental underpinnings (e.g., Rothbart & Ahadi, 1994). Although undercontrol is sometimes associated with vulnerability (e.g., Block’s, 1971, description of unsettled and vulnerable undercontrollers), the resilient undercontrolled prototype emphasized the positive aspects of this attribute, including energy and social skills. Preschool children typifying this factor did not turn into antisocial adolescents but rather into youth who functioned well interpersonally; they did not show the behavior problems that characterized Robins et al.’s (1996) undercontrolled type. Although the correlation with drug use was positive, it was low. This difference may result from the large representation of high-risk boys in the sample used by Robins et al. (1996). High self-esteem and relative absence of antisocial tendencies also characterized Hart et al.’s (1997) undercontrolled children. In adolescence, as in preschool, the individuals typifying
this personality prototype illustrated the impulsive rather than the antisocial component of undercontrol (see Robins et al., 1998, for a further description of this distinction). In sum, the individuals typifying this prototype may have adjusted to the world in a manner not pulling them toward change.

LONGITUDINAL PERSONALITY CORRELATES OF PRESCHOOL BRITTLE PERSONALITY PROTOTYPE
The very few significant age-14 CAQ correlates associated with this prototype may be due to chance and were not interpreted. The correlations with IQ remained negative. Summary of the brittle personality prototype. This prototype predicted few developmental outcomes with the exception of relatively low intelligence. Hart et al. (1997) also reported relatively weak results for their third type. As noted above, factors extracted late may be conceptually less well defined and less reliable than factors extracted early. In addition, relatively few individuals received high loadings on this personality prototype and the rank order of the many low loadings may not be reliable. Correlations involving this factor might, therefore, for psychometric reasons, not be strong. Internalizing problems—akin to those characterizing brittle and overcontrolled individuals—are also likely to fluctuate over time (Ollendick & King, 1994). Both psychometric and theoretical issues may therefore have contributed to the weak developmental outcomes for this prototype.

DISCUSSION
This study examined four issues: (a) Could psychologically coherent personality prototypes be discerned as early as in preschool (i.e., the issue of coherence)? (b) Did our preschool personality prototypes converge with personality prototypes identified in samples of slightly older participants (i.e., the issue of replicability)? (c) Did individuals typifying each personality prototype show theoretically meaningful relations to performance on experimental tasks (i.e., the issue of construct validity)? and (d) Did individuals typifying each personality prototype show different developmental outcomes (i.e., the issue of developmental implications)? Three psychologically coherent personality prototypes were identified. Strong to moderate convergence
with typologies from other studies was observed. Children typifying each personality prototype showed theoretically meaningful, although less than perfect, relations to experimental procedures of ego resiliency, ego undercontrol, and IQ. Preschool children typifying the overcontrolled resilient factor were, as adolescents, shy and inactive, but also dependable, conscientious, and intelligent. In contrast, preschool children typifying the resilient undercontrolled personality prototype were, as adolescents, active, sociable, nonconforming, and extraverted. As expected, impulse control showed greater longitudinal consistency than resiliency. This study adds to a growing literature indicating that typologies developed as early as preschool anticipate adolescent adjustment (e.g., Asendorpf & van Aken, 1999; Caspi & Silva, 1995). We recognize that the size of the correlations between the preschool personality prototypes and the personality outcomes at age 14 were moderate. Caspi and his colleagues in their typological study of 3-year-old children also reported relatively small effect sizes over time (Caspi, 2000). However, in evaluating these longitudinal results, two points should be recognized. First, personality outcomes in adolescence are likely to be influenced by factors other than the constellation of personality attributes in preschool. Ahadi and Diener (1989) showed why effect sizes, by mathematical necessity, often have to be small when the outcome variable is multidetermined. Second, “because the effects of personality differences accumulate over a lifetime, a focus on a single point in time will result in an underestimate of the extent of continuity in behavioral development” (Caspi, 2000, p. 168). Is There a Replicable Typology of Persons? Although this study identified personality prototypes comparable to those found in other studies, personality prototypes must not be prematurely reified as sampleindependent personality descriptors or as authentic substantive entities. The Q-factor approach is sensitive to the sampling of persons and the results may therefore describe samples as much as individuals. Even though similar verbal labels are used in different studies, the exact nature of corresponding types nonetheless varied. For example, although the undercontrol label has been used in several studies to identify a specific type (e.g., Hart et al., 1997; Robins et al., 1996), its most defining personality attributes still differed across studies despite moderately high convergence correlations. This lack of complete content overlap occurred even for the first and most replicable factor. Although our first factor correlated .75 with Robins et al.’s (1996) first factor, only 5 CCQ items were included among the 10 most and 10 least characteristic items that defined this factor in both studies. Even high factor convergence correlations may conceal tangible differences.

The strongest evidence for the existence of these three personality prototypes comes from studies that have used the California Child Q-sort. The CCQ was developed to provide extensive coverage of ego resiliency and ego control. It is therefore encouraging that three personality prototypes were closely recaptured by Harrington, Chin, Rickey, and Mohr (1999), who used Gough and Heilbrun’s Adjective Check List (Gough & Heilbrun, 1965). Thus, the three personality prototypes (resiliency, undercontrol, and overcontrol) do not seem uniquely dependent on the CCQ (see also Asendorpf & van Aken, 1999, p. 830). Nonetheless, the argument that these three types constitute the basis for any typology of persons may prematurely foreclose search for different typologies.
Similar to most other person-centered studies (e.g., Asendorpf & van Aken, 1999; Hart et al., 1997; York & John, 1992), this study examined typologies identified in a single point in time: at the beginning of the study. This approach is useful when the goal, as in this research, is to predict outcomes based on early existing attributes. A typology developed at a single point in time—either at the beginning or at the end of the study—has limitations.

First, the nature of the typology itself may depend too strongly on the time period during which it was developed—early childhood typologies may not be identical to adult typologies. Second, the “single-point” approach does not build life trajectories into the very definition of the typologies themselves. Gjerde, Chang, and Kremen (1998) developed typologies simultaneously identified at three separate ages, each a decade apart. These developmental typologies, simultaneously based on data from different developmental periods, provide more differentiated portrayals of life trajectories and illustrate how the person-centered approach may bridge personality and developmental research. Methodological Caveats Consistent with the majority of person-centered studies,
inverse factor analysis was employed to generate the personality prototypes. In contrast to R factor analysis, inverse factor analysis requires more variables than participants (Bailey, 1994). This assumption is seldom satisfied. Given the high number of participants relative to variables in most person-centered studies, the high replicability of the three personality prototypes across studies is promising. These findings notwithstanding, students of person typologies might benefit from multiple classification methods to avoid placing “all research eggs . . . in the same methodological basket” (Nunnally, 1978, p. 625). Other methods have shown promise (e.g., Fraley & Waller, 1998). This study identified personality prototypes at a single time period. It can therefore not estimate the continuity of the personality prototypes or the stability of group membership across time. Type membership may change over time (e.g., Gjerde et al., 1998). The emergence of personality types is also a crucial issue for future research. The identification of the conditions under which group membership changes (or remains stable) may help us understand the developmental unfolding of different types (e.g., Hart et al., 1997).

Coda
Developmental and personality research would seem to benefit from a greater focus on (a) the person as a basic analytical unit and (b) the diverse developmental pathways characterizing different homogeneous groups of individuals. However, the person-centered concept carries different meanings to different researchers. Consistent with previous studies (e.g., Asendorpf & van Aken, 1999; Hart et al., 1997; Robins et al., 1996; York & John, 1992), this study used inverse factor analysis to identify coherent and replicable personality prototypes. But once these prototypes were identified, they were—as in similar studies—used in a variable-centered way in that person loadings were correlated with other variables. Hart et al. (1997) noted that once personality types have been identified, intellectual inquiry necessarily must return to a variable-centered approach. For example, is “the undercontrolled child’s aggressiveness primarily the consequence of a need to defend extremely high self-esteem?” (p. 204). This study may therefore be viewed as combining both person-centered and variable-centered analytical strategies. In general, the relationship between variable-centered (or nomothetic) laws, which holds for groups, and ideographic laws, which holds for specific individuals, may be both more complex and less contradictory than generally believed. Meehl suggested in 1954 that “behavioral laws are (a) nomothetic in their form for a given group, (b) ideographic in their parameters, and (c) strongly ideographic in their end terms, which refers to response properties of the organism” (Wiggins, 1973, pp. 148- 149). Allport (1937), as well, did not argue that general laws precluded uniqueness. Wiggins (1973, Chap. 4) provides an excellent discussion of these issues. Some psychologists may not consider this study as truly person centered. We grouped participants into three homogenous personality prototypes. Future studies, however, might do well to include case examples of each personality prototype. Two individuals who both received high loadings on the same personality prototype may still have different life stories to tell, construct their lives differently, or hold different personal goals. Future research might benefit from integrating personality typologies with personal concerns and narrations of the self (i.e., Level II and Level III of personality, as described by McAdams, 1995). Furthermore, identification of personality prototypes in combination with in-depth case studies representative of each prototype might bridge the personological tradition—with its focus on individuals in their life context—with the approach taken in this study. Greater reliance on narrative methodologies appears to be a particularly promising avenue to pursue to achieve this aim.

Measures
Measuring child personality: The CCQ. Three nursery school teachers used the CCQ (Block & Block, 1980) to evaluate each participant at age 3. Three different nursery school teachers evaluated the children at age 4. Each teacher had known the child for at least 6 months. The CCQ is widely used in developmental and personality psychology (e.g., Gjerde, 1995; Hart et al., 1997; Robins et al., 1996). The assessors were provided with 100 statements about the characteristics of children, each printed on a separate card. The assessors described each child by arranging theCCQitems into a forced distribution using nine categories, ranging from highly uncharacteristic to highly characteristic of the child being described. The CCQ descriptions were aggregated for each child separately at each of the two ages. The two aggregates were then aggregated and this final age-3/age-4 aggregate was used in subsequent analyses. The alpha of theCCQitem, based on correlations among nursery school teachers, averaged .65 both at age 3 and age 4. The average CCQ item reliability was .72. TheCCQis an ipsative procedure; there is a “scale for every individual and a population of an individual trait score is distributed about that individual’s mean” (Guilford, 1952, p. 30). A Q-item reflects the salience relative to other Q-items with reference to a particular person. Thus, the Q-sort can be said to provide personcentered rather than variable-centered information (Block, 1971).

All assessors sorted the CCQ items into a forced distribution that stipulates the number of cards included in each of the nine piles. The use of this identical scaling method provides all participants with identical means and standard deviations across the 100 items. Thus, in inverse factor analysis, standardizing the columns in the transposed matrix is unnecessary. This is important because correlations among persons are influenced by differences among variable means (e.g.,Waller&Meehl, 1998). In sum, the forced distribution Q-sort method is uniquely suited for inverse factor analysis (Asendorpf & van Aken, 1999). Measuring preschool ego resiliency and ego undercontrol using the CCQ. Three psychologists used the CCQ to describe a prototypical ego resilient child (α = .91) and a prototypical ego undercontrolled child (α = .90). Each participant’s CCQ profile was then correlated separately with each of the two personality prototype definitions. If this correlation was high, the participant could be described in terms of this construct; if this correlation was low or negative, the participant was dissimilar from this construct (see Onishi, Gjerde, & Block, 2001, for a detailed description of this method). For the participants included in this study, the average ego resiliency score was .45 (SD = .32) and the average ego undercontrol score was .08 (SD = .32). These scores—based on the average correlation of the two prototype definitions with each participant’s overall Q-sort profile across the sample—are comparable to those reported by Robins et al. (1996) and Hart et al. (1997): .40 and .36 for ego resiliency and .06 and .09 for ego undercontrol, respectively.

Measuring adolescent personality: The CAQ. The CAQ shares the same psychometric principles as the CCQ, but the 100 items are written to reflect characteristics of adolescents and adults. At age 14, five advanced graduate students used the CAQ (Block, 1961/1978) to describe the personality characteristics of each participant. Prior to the assessment, the graduate students received thorough training in the Q-sort methodology and the content of each item was discussed. The assessors described the participants after having observed them performing in a variety of experimental procedures on four occasions, each lasting between 2 and 3 hr, in a laboratory setting. An interview also was conducted by one of the assessors. These five independent CAQ descriptions were averaged for each participant and this aggregate was used in subsequent analyses. Developing adolescent personality constructs using the CAQ. Knowledgeable psychologists used the CAQ to provide definitions of the following personality constructs: ego resiliency, ego undercontrol, shyness, and activity level. Shyness and activity level were included because they relate directly to ego undercontrol. Expert descriptions also were obtained for the Big Five trait dimensions: Agreeableness, Extroversion, Emotional Stability, Conscientiousness, and Openness to Experience. No psychologist defined more than one construct. Scores for each participant on each of these personality constructs were developed using the method described above for the CCQ-based measures of ego resiliency and undercontrol. The alpha reliabilities exceeded .85 for all constructs.
Measuring Preschool Ego Resiliency Using Laboratory Measures The motor inhibition task. This task (Maccoby, Dowley, Hagen, & Degerman, 1965) measured the child’s ability to change from a modal tempo to a slower tempo according to instructions. The child was first asked to draw a line, walk, and wind a toy without instructions, followed by instructions to perform these activities “very, very slowly, just as slowly as you can.” The final inhibition score is a composite regression-adjusted score that reflects how long it took the child to complete the task under the slow-speed instruction conditions, controlling for the child’s speed under the regular (or noninstruction) conditions. Estimated time was approximately 12 min.

The egocentrism task. This task (Flavell, Botkin, Fry, Wright,&Jarvis, 1968) assessed a child’s ability to predict which objects other persons can or cannot see. The examiner covered different parts of a double-sided picture board and asked the child what the examiner could see. An egocentric response was defined as one in which the child chose a picture that could be seen from his or her side but not from the experimenter’s side. Estimated time was approximately 5 min. The Lowenfeld mosaics test. This task (Lowenfeld, 1954) assessed the aesthetic quality of mosaic constructions. The child was given a tray and 132 geometric shapes and asked to “do something with the pieces on this tray.” The mosaics were evaluated both for imaginativeness and structure. In this study, we only used the imaginativeness ratings thought to reflect ego resiliency. Four judges, whose ratings were subsequently composited, scaled the mosaic photographs for imaginativeness using a sevencategory Q-sort. Estimated time was approximately 12 min.

Measuring Preschool Ego Undercontrol Using Laboratory
Measures
The actometer task. This task (Schulman & Reisman, 1959) was designed to measure activity level. An actometer is a self-winding watch activated by a child’s
movements. The participants wore the actometer on the wrist of the nonfavored hand for 2 hr. Four actometer measurements, each separated by 1 week, were conducted and then composited. The delay-of-gratification task. In this task (Funder, Block, & Block, 1983), the child received an enticingly wrapped gift. He or she was then given a puzzle task and told that she or he could have the gift later. The delay-ofgratification score is a composite based on (a) the number of verbal behaviors toward the gift, (b) the number of physical behaviors toward the gift, (c) the time before the child took the present, and (d) the swiftness of opening the present. Estimated time was approximately 5 min. Wechsler intelligence tests. The Wechsler Preliminary and Preschool Scale of Intelligence Test (WPPSI) was administered at age 4, the Wechsler Intelligence Scale for Children (WISC) was administered at age 11, and the Wechsler Adult Intelligence Scale-R (WAIS-R) was administered at age 18 (Wechsler, 1981). Drug usage. The videotaped age-14 interview included questions about a wide variety of issues (e.g., family relations, peers, and schoolwork). The participants also were asked about their usage of illegal drugs, including both marijuana and “harder drugs,” such as heroin and cocaine. Marijuana use was measured on a 6-point scale: never used marijuana (0) to used more than once a week (6).
“Harder drugs” was measured on a 2-point scale: never used (1) to used once or more (2). Two raters who showed near exact agreement separately coded drug use. (Block, Block, and Keyes [1988] provide a complete description of the development of the drug measures and relevant descriptive statistics.) We initially conducted separate analyses of marijuana and harder drugs use. Because the relations between the personality prototypes and the two drug measures were virtually identical, we composited the two drug measures (α = .91).

This study classified for resemblance 102 preschool children, who were described by their nursery school teachers using the California Child Q-sort. Inverse (Q) factor analysis identified three personality prototypes initially defined in terms of ego resiliency and ego undercontrol: overcontrolled resilient, resilient undercontrolled, and brittle. These personality prototypes showed strong to moderate similarity with typologies obtained in comparable studies and theoretical meaningful relations with experimental measures of ego functioning and IQ. Ten years later, as adolescents, overcontrolled resilients were shy and restrained yet conscientious and intelligent; resilient undercontrollers were extraverted, assertive, and impulsive; and brittles were relatively unintelligent. The discussion focused on the several meanings of person-centered methods, the sample-dependence of personality typologies, and the complementary contributions made by person versus variable-centered analytical strategies in the study of human development.

Research on personality development has mostly been governed by a variable-centered analytical strategy. This approach examines relations among variables (most commonly conceptualized as traits) and individuals’ relative (or rank-order) standing on one or several trait variables. Although variable-centered studies have provided invaluable knowledge, it has—as any other method— limitations. For example, it is restricted to providing information on aggregates of individuals, or on what Lewin (1931) once called the mythical “average child.” Mishler (1996) also has criticized reliance on group means, arguing that these “inferences lead to an idealized, universal child” (p. 78) and called for case-based studies that, in his view, maintain greater respect for agency, history, and intentionality. Recently, a complementary approach to the study of personality has been receiving renewed attention (e.g., Cairns, Kagan, & Bergman, 1998). This orientation— typically referred to as person centered—uses both quantitative and qualitative methodologies. Examples include inverse factor analysis (Block, 1971), narrative methodologies (Hauser, 1999; McAdams, 1999), and biographical studies of lives (Runyan, 1982). The personcentered approach has a long tradition; it can be traced back at least as far as to Murray’s (1938) personology, the ideographic approach of Allport (1937), and more recent critiques for not using the individual as the unit of analysis (Carlson, 1971). Recent person-centered studies have attempted to identify homogeneous and replicable typologies of individuals (e.g., Asendorpf & van Aken, 1999; Hart, Hofmann, Edelstein, & Keller, 1997; Robins, John, Caspi, Moffitt, & Stauthamer-Loeber, 1996). Robins, John, and Caspi (1998), in particular, argued strongly for the existence of three basic personality types: resilients, undercontrollers, and overcontrollers. Important, albeit not incontestable, support for these types has been obtained in samples differing both in age and
national origin (e.g., Asendorpf&van Aken, 1999; Caspi & Silva, 1995; Hart et al., 1997; Robins et al., 1996). Conceptual Framework: Ego Resiliency and Ego Control Several recent person-centered studies (Asendorpf & van Aken, 1999; Hart et al., 1997; Robins et al., 1996) have defined their typologies in terms of two personality constructs: ego resiliency and ego control (Block & Block, 1980). Ego resiliency refers to an individual’s ability to adapt flexibly to changing environmental circumstances. In contrast, ego control refers to an individual’s threshold of impulse expression and ranges from overcontrol (i.e., high threshold) to undercontrol of impulse expression (i.e., low threshold). Overcontrol refers to “excessive containment of impulses, delay of gratification, inhibition of action and affect, and insulation from environmental distractors,” whereas undercontrol refers to “insufficient modulation of impulse, inability to delay gratification, and immediate and direct expression of motivation and affects, and vulnerability to environmental distractors” (Block & Block, 1980, p. 43). To compare our personality prototypes with those obtained in previous studies, this study also initially defined each personality prototype in terms of ego resiliency and ego control.

Personality Typologies: Discrete Categories Versus “Fuzzy” Entities Most person-centered studies have assigned individuals to nonoverlapping groups based on their highest factor loading (e.g., Robins et al., 1996), thereby assuming that personality typologies are best considered as discrete, mutually exclusive, and nonoverlapping categories. In contrast, York and John (1992) argued that “category membership need not be ‘all or none’ but is a matter of degree: individuals differ in their degree of fit to the category personality prototype, with some being more prototypical instances than others” (p. 495). This procedure is consistent with Rosch’s view (1978) of natural categories as “fuzzy” entities and Meehl’s (1995) argument that latent taxons need not have clear-cut “surface” indicators. This study adopted this latter procedure. Because our typologies are therefore not mutually exclusive and the category boundaries not discrete, we use the term “personality prototype” rather than “personality type” (see York & John, 1992, for a detailed description of this approach). The Aims of the Current Study With few exceptions (Asendorpf & van Aken, 1999; Caspi, Henry, McGee, Moffitt, & Silva, 1995; Hart et al., 1997), current typologies are based on participants ranging in age from adolescence through middle age (e.g., Block, 1971; York & John, 1992). Typologies, however,
may not be independent of age. For example, Magnusson’s (2000) holistic notion of individuals as organized wholes implies the presence of “personality crystallization,” whereby increasing age leads to clearer resemblance within groups of persons and clearer distinctions among groups of persons across time. Thus, it is uncertain whether typologies developed early in life are as psychologically coherent as those based on older individuals forwhomgreater differentiation in personality structure can be expected. Overview of the Current Study Coherence and replicability. This study consists of three parts. The first part examined two issues: (a) Can psychologically coherent personality prototypes be discerned as early as in preschool (i.e., coherence)? and (b) Do our preschool personality prototypes converge with those identified in other samples (i.e., replicability)? To address these issues, we (a) derived preschool personality prototypes by means of inverse factor analysis, (b) examined their replicability within the current sample, (c) interpreted the psychological content of the personality prototypes, and (d) studied their similarity vis-à-vis personality types obtained in three other studies that also used inverse factor analysis to identify their typologies and defined them in terms of ego resiliency and ego control (Asendorpf & van Aken, 1999; Hart et al., 1997; Robins et al., 1996). Evaluating construct validity using laboratory procedures. The second part focused on the construct validity of the personality prototypes obtained in this study. If different measures based on different kinds of data converge in their implications, greater confidence can be invested in the validity of a construct. Thus, we evaluated whether the three personality prototypes—based on observer observations provided by nursery school teachers— showed theoretically meaningful relations to performance on standardized, objective laboratory procedures specifically devised to index ego resiliency and ego undercontrol.

Developmental implications a decade later. The third part investigated the developmental outcomes of each personality prototype a decade later once the participants had reached adolescence. Very few longitudinal studies have examined the developmental implications of preschool personality prototypes. In their German sample, Asendorpf and van Aken (1999) reported that although the overcontrolled type scored high as preschoolers on IQ, school performance, and self-esteem, they declined on all three attributes over time. In their New Zealand sample, Caspi and Silva (1995) found undercontrolled preschoolers to be impulsive, aggressive, and lacking good interpersonal relations as adolescents; inhibited preschoolers to be low on aggression and impulsivity as adolescents; and well-adjusted preschoolers to be resilient and self-confident as adolescents. In their study of Icelandic children, Hart et al. (1997) reported that the resilient type improved in academic performance, the undercontrolled type showed increased aggressive problems, and the overcontrolled type tended to withdraw from social interaction over time. The current study is the first to examine the developmental implications of preschool personality prototype membership in a North American sample.

Previous research and theory offer two alternative models of the structure of essentialist beliefs. Gelman’s (2003) work implies a unifactorial structure, as she formed a composite essentialism score by combining all of her items. Alternatively, previous work by Haslam et al. (2000, 2002) favors a model containing distinct and orthogonal dimensions of naturalness and entitativity consistent with Rothbart andTaylor’s (1992) description of essentialism as having distinct aspects of inalterability and inductive potential. However, this work exclusively addresses social categories, and the two-dimensional structure may not apply in the personality domain. If a different structure applies in that domain, then essentialist thinking might have different determinants and implications from those documented in the study of social categories. For example, essentialist beliefs about personality might not have the same links to prejudice and devaluation. A unifactorial structure would also cast doubt on the applicability of concepts of natural kind and entitativity in the personality domain. Given the plausibility of both one- and two-dimensional models, we made no specific structural predictions beyond an expectation of overall covariation among the essentialist beliefs.

Study 1 also tests three hypotheses about possible correlates of personality essentialism. Little is known about why some social distinctions are essentialized more than others and some possibilities—for example, visible morphology for race and gender (Rothbart & Taylor, 1992), descent and endogamy for ethnicity (Gil-White, 2001), abrupt transformation (Keil et al., 1999) for disease—do not apply to personality characteristics. Our hypotheses were, therefore, speculative. First, we hypothesized that affective personality characteristics should tend to be more essentialized than others because, according to folk psychology, emotions are intimately linked to the person’s biology (D’Andrade, 1987). As a result of this embodiment, emotion-related personality characteristics should be understood in a more naturalized manner than others. This prediction about lay conceptions of personality accords with scientific conceptions of temperament, which is normally understood to be composed of emotional traits that are substantially heritable and biologically based (Clark & Watson, 1999). Our second and third hypotheses derive from the recent work of Leyens et al. (2000, 2001), who argued that people selectively attribute a distinctively human essence or nature to themselves and their ingroup. By implication, personality characteristics should be essentialized if they are understood to be aspects of human nature. Because human nature is a normative concept, representing valued and in principle, widely shared human attributes, personality characteristics that are understood as aspects of it should be relatively desirable and prevalent. Thus, positive (Hypothesis 2) and prevalent
(Hypothesis 3) characteristics should be essentialized more than others because they are more likely to be seen as elements of human nature.

Neither of these hypotheses is self-evident. Ethnic and sexual minorities—groups both devalued and of low prevalence—have been the focus of much past research on essentialist beliefs. It has often been argued that essentialist beliefs play an important role in prejudice (e.g., Allport, 1954; Rothbart & Taylor, 1992), implying that they are associated with the attribution of undesirable characteristics; and one study finds that more essentialized social groups tend to have lower social status (Haslam et al., 2000). Nevertheless, the logic of the work of Leyens et al. (2000, 2001) is that aspects of normative human nature—of which personality characteristics are more likely candidates than particular ethnic or sexual identities—should tend to be essentialized.

Method Participants. Seventy-three undergraduate psychology students (58 women, 15 men), mean age 21.5 years (SD = 1.6), participated in the study as part of a laboratory session. Materials. All participants completed a questionnaire in which they rated 80 personality descriptors. The descriptors were systematically selected to yield a broad and evaluatively diverse sample based on an inclusive understanding of personality that extends beyond standard trait models (see Table 1). Forty terms were sampled from adjectival markers of the Big Five trait dimensions developed by John and Srivastava (1999), taking 4 descriptors from each pole of every dimension. Twenty terms were sampled from Schwartz’s (1992) value taxonomy, taking 2 from each value segment. Ten terms were derived from the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) personality disorders, taking 1 emblematic term for each disorder. Finally, 10 negative terms were sampled from Benet-Martínez and Waller’s (2002) fivedimensional model of highly evaluative terms. Participants rated the personality descriptors on subsets of nine items. Six of these items assessed essentialist beliefs and were based on the Essentialist Beliefs Scale developed by Haslam et al. (2000, 2002). That scale’s original “uniformity” item was modified to refer to the cross-situational consistency of behavior rather than the similarity of category members because both refer to forms of homogeneity. All items were rated on 7-point Likert-type scales (1 = strongly disagree and 7 = strongly agree) with the exception of biological basis, and the items were written as follows: Discreteness: “People either have this characteristic or they do not: those who have it are a distinct type of person” Biological basis: “To what extent is this characteristic based on the person’s biological or genetic make-up? Write one of the following percentages in the space provided” (percentages from 0 to 100 in increments of 10) Immutability: “It is easy to change this characteristic: it is not a fixed attribute of the person” (reverse scored) Informativeness: “This characteristic has broad ramifications: it influences people’s behavior in a wide variety of situations and in many aspects of their lives” Consistency: “People who have this characteristic will tend to display it in a consistent manner, showing it in different situations and with different people” Inherence: “This characteristic is a deeply-rooted part of the personality: it lies deep within the person and underlies the person’s behavior” Three additional items were written to assess variables hypothesized to be correlates of essentialist beliefs about personality. These items assessed the social desirability, population prevalence, and affectivity of personality characteristics: Desirability: “How desirable or positive is this personality characteristic?” (1 = extremely undesirable and 7 = extremely desirable)
Prevalence: “What percentage of the general population could reasonably be described as having this characteristic? (please write a number in the space provided)” Affectivity: “Some personality characteristics are primarily emotional (i.e., about emotions, moods and feelings) and some are primarily cognitive (i.e., about beliefs and ways of thinking). Rate the characteristics on the extent to which they are primarily emotional or cognitive” (1 = primarily emotional and 7 = primarily cognitive; reverse scored) Each participant completed a three-page questionnaire containing a cover sheet and two rating pages, each listing the 80 personality descriptors and with one item printed at the top. Design and procedure. Each participant’s questionnaire contained a randomly assigned pair of the nine items, requiring a total of 160 ratings. The order of items in each pair was also randomized. The 80 personality descriptors were presented in a standard random order or its exact reverse, and these two orders were also randomly assigned within each questionnaire. Consequently, each item was equally likely to be rated by each participant, in either first or second position, with either of two descriptor orderings. Participants completed the questionnaire in a classroom setting, in three groups of 18 to 29. Most finished within 20 minutes, after which they were extensively debriefed.

Results
The focus of the study was on shared essentialist beliefs about personality and on differences among the 80 personality descriptors rather than among participants, so ratings of the descriptors were aggregated across the subsample of participants (mean n = 16.2) who rated them on each item. Consequently, mean ratings of each descriptor on each of the nine items served as the basis for the data analyses. These aggregated ratings are meaningful to the extent that participants agree in their ratings. If agreement is adequate, a testable requirement, then the aggregated ratings yield higher levels of reliability than the individual ratings on which they are based. Aggregation is particularly important where ratings are apt to be somewhat difficult to make, as in the sometimes complicated conceptual judgments (i.e., treating each rater as akin to a test item), are presented in Table 2. Reliabilities were generally moderate to very strong (mean α = 0.77), with ratings of immutability alone being weak (α = 0.40). Table 2 also presents mean aggregated ratings of the 80 descriptors. Mean ratings on the Likert-scaled items fall close to the scale midpoint of 4. “Biological makeup” was attributed a substantial role in the personality characteristics (mean 36.2%), which were generally judged to apply to a large minority of the population (mean 42.9%). One-way ANOVAs with post hoc Scheffé comparisons (Bonferroni corrected) indicated that the descriptor types differed on four of the six essentialist belief items. In every case, the highly evaluative terms were essentialized less than the trait, value, and personality disorder descriptors. Predictably, the highly evaluative and personality disorder descriptors were judged to be more deviant—infrequent and undesirable—than the value and trait descriptors. Intercorrelations among the nine items across the 80 descriptors are presented in Table 3, which indicates that the essentialist belief items are intercorrelated as hypothesized. Ten of the 15 correlations are statistically significant with a mean value of 0.34, which rises to 0.49 when correlations are disattenuated for unreliability. A principal components analysis indicated that the six essentialist belief items composed a single factor (48.9% explained variance) based on the scree test (eigenvalues 2.94, 1.34, 0.75, 0.39, 0.37, 0.22). All items loaded substantially on the factor (> 0.42) with the exception of immutability (0.21), a finding that might be explained by the item’s unreliable assessment. The unifactorial structure was strongly supported by an iterative factor analysis (eigenvalues 2.68, 0.95, 0.25, 0.10, 0.03, 0.00). This structure also held when analyses were restricted to the 40 Big Five traits. Factor scores of the 80 descriptors from the first principal component were therefore employed as an essentialism index, which summarizes the extent to which the descriptors were essentialized on the six items. Scores of the descriptors on this index, averaged across Studies 1 and 2, are presented inTable 1. The essentialism index was used to test the study hypotheses. Consistent with prediction, more desirable personality characteristics were essentialized more, r = 0.54, p < .001, as were characteristics rated as more prevalent, r = 0.50, p < .001. Contrary to prediction, however, more emotion-based characteristics were not more essentialized, r = 0.10, ns, although Table 3 indicates that they were judged to be more biologically based and inherent. Inspection of Table 3 also shows that desirability, prevalence, and affectivity are intercorrelated, rendering univariate tests potentially unreliable. Consequently, a simultaneous multiple regression analysis was conducted with the three variables serving as independent variables. As a set, these items powerfully predicted the essentialism index, F(3,76) = 14.1, p < .0001, R = 0.60, and each item had an independent effect (desirability: β = 0.39, p = .003; prevalence: β = 0.26, p = .044; affectivity: β = 0.21, p = .031). Thus a multivariate analysis supports all three hypotheses.

Discussion
The findings of Study 1 offer substantial support for its hypotheses. The essentialist belief items covaried strongly and in a unifactorial manner, indicating that people’s thinking about personality reflects a coherent essentialist ontology that is systematically applied more to some characteristics than others. Thus, a set of beliefs that had been found to covary in studies of social categories also covaried for characteristics that are usually seen as personal rather than social, as dimensions rather than categories, and as adjectives rather than nouns. Simply stated, personality characteristics understood to be biologically based, discrete, immutable, informative, consistent, or deeply rooted also tend to be understood in all of the other ways as well. In addition, the extent to which personality characteristics were essentialized was predictable from their desirability, prevalence, and emotional basis. The last effect was relatively weak and did not emerge on a univariate test, but it implies that affective characteristics are, as D’Andrade (1987) proposed, more directly linked in folk psychology to our underlying, embodied nature than more cognitive characteristics. The desirability and prevalence effects were more robust. Although essentialist beliefs are often invoked to account for beliefs about deviant and devalued minorities, in the personality domain, they appear to be held primarily about valued and widely shared characteristics. The work of Leyens et al. (2000, 2001) on “human nature” offers a way to understand these effects. Almost by definition, our fundamental nature as human beings should be revealed in what we tend to have in common and in what we value. By this account, desirable and prevalent characteristics are especially essentialized because they constitute aspects of human nature. Leyens et al. (2000) listed intelligence and language as candidates for distinctively human essences, and it is interesting that the 2nd and 3rdmost essentialized descriptors in Study 1 were intelligent and talkative. Several other highly essentialized descriptors—independent (1st), creative (4th), imaginative (6th), ambitious (7th)—also arguably represent distinctively human attributes of autonomy, originality, transcendence of the senses, andfuture-orientedstriving.1

STUDY 2
Study 1 demonstrates that people distinguish among personality characteristics in a coherent essentialist fashion and supports three hypotheses about factors that may contribute to the greater essentializing of particular characteristics. However, it remains to be seen whether essentializing personality has a bearing on social cognition and behavior. If a coherent essentialist understanding is held for some characteristics more than others, but this understanding has no further implications, then Study 1’s findings have limited relevance. One plausible general hypothesis about the implications of essentialist beliefs is that more essentialized personality characteristics should be particularly important bases for social inference and judgment. This hypothesis can be justified on several grounds. First, highly essentialized characteristics should be understood as informative and, hence, valuable for making wide-ranging inferences about behavior. Second, they should be viewed as homogeneous (consistent) in their manifestations and, hence, likely to yield relatively accurate behavioral predictions across situations. Third, the perceived immutability of essentialized characteristics should make them reliable sources of social inferences over time. Fourth, their inherence and discreteness should make highly essentialized characteristics seem to capture fundamental and defining aspects of people. For all of these reasons, more essentialized personality characteristics might be understood as particularly fundamental—high in generality, significance, and reliability. If essentialized personality characteristics are especially important for social cognition and behavior, this importance could be manifest in several ways. First, essentialized characteristics might be viewed as particularly central to personal identity, judged to be core aspects of the person that define who he or she is. Allport (1937) raised this issue of trait centrality to refer to the fact that particular traits are especially prominent within persons. In this spirit, Trafimow and Finlay (2001) assessed trait importance by having people rate how important certain traits were for how they thought about themselves. Essentialized personality characteristics might be central in a more general way, seen as especially salient and identity-determining for whoever possesses them. Asecond, more interpersonal manifestation of a characteristic’s importance is its perceived utility for judging other people. More “relationally important” characteristics, in this sense, are those that people believe to be most useful or valuable to know in evaluating potential inter- actants. Relational importance as defined here resembles “trait centrality” as employed by Asch (1946) in his pioneering research on impression formation. More central traits, in his sense, are those that exert a relatively potent effect on impressions, and we might expect that these are the traits that social perceivers would want to know about in judging an unfamiliar person. If essentialized personality characteristics are high in relational importance, then people would be especially keen to find evidence pertaining to them when making such judgments.

A third form of importance involves communication. The pragmatics of communication suggest that people should normally endeavor to communicate the most relevant and informative material to their interlocutors (Grice, 1975). By implication, if they are describing a person to someone else, people should select or emphasize those personal attributes that are most vital to know. If essentialized personality characteristics are particularly important in this sense, then they should be more communicable (Schaller, Conway, & Tanchuk, 2002). Study 2 was designed to test the broad hypothesis that more essentialized personality characteristics are judged to be more important. Importance was assessed as centrality, relational importance, and communicability, as defined above. All three subsidiary hypotheses were also expected to hold when other factors that might influence social importance were statistically controlled. For instance, a personality characteristic’s importance for some purposes might in part be a function of its desirability or of its prevalence, as examined in Study 1. Communicators might tend to mention a person’s more positive attributes out of politeness, whereas undesirable characteristics might be considered particularly important in forming impressions (Hamilton & Zanna, 1972). Characteristics that are central to identity might be those that are particularly distinctive (i.e., low prevalence; Blanton & Christie, 2003). Thus, we predicted that essentialized characteristics would be judged to have high
importance independent of their social desirability and prevalence. Finally, Study 2 aimed to replicate the structure of essentialist beliefs about personality, employing the same items and characteristics as in Study 1.

Method
Participants. Eighty-one undergraduate psychology students (64 women, 17 men), mean age 22.3 years (SD = 4.2), participated in the study as part of a laboratory session. Materials. Participants rated the 80 personality descriptors from Study 1 on questionnaires that closely resembled those completed in that study. The same six essentialist belief items were employed, but participants also rated three new items assessing the importance of the personality characteristics. Importance was operationalized in three distinct ways: a characteristic’s centrality to the identity of the person who possesses it, its relational importance (i.e., the extent to which it would be desirable for judging a prospective interactant), and its communicability when describing someone who had it to another person. These items were written as follows: Centrality: “This characteristic is a central aspect of a person’s personality: if you have it, it defines who you are” (1 = strongly disagree and 7 = strongly agree) Relational importance: “Imagine you are about to meet someone new who you will have to interact with for a substantial period of time. How important would it be for you to know that the person has this characteristic?” (1 = not at all important and 5 = extremely important) Communicability: “If you knew that a person had this characteristic, how likely would you be to mention it when describing the person to someone else?” (1 = very unlikely and 7 = very likely) Design and procedure. The questionnaires were constructed according to the same design as in Study 1. Again participants rated a randomly assigned and ordered pair of the nine items, with two possible reversed orderings of the 80 personality descriptors. Participants completed the questionnaires in a classroom setting, in four groups of 15 to 27 participants, followed by debriefing.
Results
As in Study 1, ratings were aggregated across the subsamples of participants who rated each item (mean n = 18.0). Reliabilities and mean ratings across the 80 personality descriptors are presented in Table 4. All reliabilities were satisfactory (mean α = 0.79), indicating that the aggregate ratings offer reliable estimates of shared beliefs about the personality descriptors. The reliability of immutability ratings was notably better than in Study 1. As in Study 1, one-way ANOVAs with post hoc Scheffé comparisons (Bonferroni corrected) indicated that the highly evaluative personality descriptors scored lower than the other descriptor types on four of the six essentialist belief items. The same pattern held for the centrality and communicability items. Correlations among the mean ratings across the 80 personality descriptors are presented in Table 5, which again reveals substantial intercorrelations among the six essentialist belief items (mean r = 0.50). Immutability correlated much more strongly with the other essentialist belief items than in Study 1, probably because of its improved reliability. A principal components analysis indicated that a single factor accounted for the 6 items (59.1% explained variance), according to both the Kaiser criterion and the scree test (eigenvalues 3.54, 0.95, 0.69, 0.46, 0.21, 0.16). Every item loaded powerfully (> 0.59) on this factor. To pursue the structure of essentialist beliefs about personality further, a confirmatory factor analysis compared the adequacy of a onefactor model with models containing two correlated or orthogonal factors corresponding to the natural kind and entitativity factors obtained previously (Haslam et al., 2000). The one-factor model (χ2/df = 5.52, root mean square error of approximation [RMSEA] = .239) fit substantially and significantly better than the model containing two orthogonal factors (χ2/df = 10.93, RMSEA = .355) and equally well as the model containing two correlated factors (χ2/df = 5.44, RMSEA = .237). As fit values for the two better fitting models did not differ significantly, parsimony supports the one-factor model, especially as the two factors were so highly correlated (r = 0.83) as to question their distinctness. Thus, scores on the first principal component were again employed as an essentialism index. This index correlated 0.91 with the Study 1 index, demonstrating that the component is highly replicable and yields a robust assessment of essentialist beliefs. Similarly, all of the essentialist belief items correlated very highly with the corresponding items in Study 1 (rs ranged from 0.74 to 0.85), with the exception of immutability (r = 0.39). Study 2’s additional hypotheses predict that more essentialized personality characteristics should be more important, as operationalized by the centrality, relational importance, and communicability items. These items correlated well across the sample of personality descriptors (mean r = 0.47), consistent with them all representing forms of importance. Univariate tests of the hypothesized associations were uniformly supportive. The essentialism index correlated 0.82 (p < .0001) with centrality, 0.27 (p = .014) with relational importance, and 0.69 (p < .0001) with communicability. Thus, more essentialized personality characteristics were consistently judged to be relatively important. The univariate associations between the importance items and the essentialism index might be complicated by other variables not measured in Study 2. Indeed, the desirability and prevalence ratings derived from Study 1 were strongly correlated with centrality (rs = .51 and .51, ps < .001) and communicability (rs = .53 and .42, ps < .001). To determine whether desirability and prevalence might account for the correlations between the essentialism index and the importance items, several simultaneous multiple regression analyses were conducted. In these analyses, the importance items were dependent variables and the essentialism index (from Study 2), and desirability and prevalence (from Study 1) were the independent variables. In each case, the association between essentialist beliefs and importance remained significant after desirability and prevalence were statistically controlled. Standardized beta weights for the essentialism index in the centrality, relational importance, and communicability analyses were 0.74 (p < .0001), 0.31 (p = .018), and 0.56 (p < .0001), respectively. More important
personality characteristics, therefore, appear to be more essentialized, independent of their evaluative charge and judged prevalence. Desirability independently predicted relational importance (β = –0.32, p = .044) and communicability (β = 0.24, p = .044) in these analyses, implying that people are more concerned to know about undesirable characteristics of prospective interactants and more inclined to mention desirable characteristics when describing someone to a third party.

Discussion
The findings of Study 2 clearly support the broad hypothesis that essentialized personality characteristics are judged to be particularly important and central attributes of persons. Their relatively high importance generalized across intrapersonal (centrality) and interpersonal (relational importance and communicability) domains and was not reducible to established determinants of importance, such as desirability and distinctiveness (i.e., low prevalence). Essentialist beliefs, therefore, may represent a previously unexamined determinant of the importance of personality characteristics, which may be relevant to researchers on identity, impression formation, and interpersonal communication. In short, part of what makes some attributes particularly influential in
these domains may be the ontological assumptions that people make about them. Just as people judge trait adjectives to imply greater behavioral stability and consistency than action verbs (Semin & Fiedler, 1988), they also judge some adjectives to refer to more fundamental and essence-like attributes than others.
Although it is plausible that the extent to which personality attributes are essentialized plays a causal role in determining their importance and, hence, their role in social cognition and identity, the causal arrow might point in the opposite direction. More important personality attributes, or attributes that are most often used in social judgment and communication, might come to be more essentialized. Kashima (2004), for example, demonstrated how communication can increase the perceived entitativity and essentialism of social groups. Consequently, the findings of this study, such as the association between essentialism and communicability, cannot be confidently interpreted as revealing a causal role for essentialist beliefs in this domain.

GENERAL DISCUSSION
The present studies strongly suggest that a coherent set of essentialist beliefs are held about personality characteristics, just as previous research finds them to be held about a variety of social categories. The studies, therefore, help to extend the range of domains in which psychological essentialism applies. In doing so, they join a small quantity of work that primarily examines children’s understandings of traits (e.g., Giles, 2003; Yuill & Pearson, 1998), focuses on single elements of essentialist beliefs such as inherence (e.g., Semin&Krahé, 1987), or addresses individual differences in essence-related beliefs about personality as a whole rather than differences among personality characteristics (e.g., Levy et al., 1998). Moreover, the studies demonstrate that essentialist beliefs about personality are not only held, but are also held preferentially for particular kinds of characteristics and have several social-cognitive implications. Just as academic trait theory presents a somewhat essentialist view of traits, so do implicit personality theories apply essentialist assumptions, as Gelman (1992) proposed. Although the two studies provide good support for the coherence of essentialist beliefs about personality, the unifactorial structure of these beliefs differs from the two-dimensional structure obtained in previous work on social categories (Haslam et al., 2000, 2002). Different belief structures may hold in the personality and social category domains, such that the distinct entitativity and natural kind dimensions obtained in the latter are somehow fused in the former. Personality characteristics that are “naturalized” (i.e., understood to be biologically based, fixed, and discrete) also appear to be understood as underlying entities (i.e., inherent, informative, and consistent), whereas these two understandings are largely independent for social categories. Reasons for this apparent divergence are unclear, but it supports the view that essentialist beliefs may be differently organized in different domains. One interpretation of the tendency for people to essentialize some personality characteristics more than others is that they treat some characteristics as more “real” than others. If this is the case, and a realist view of personality characteristics (Yuill, 1992) is applied selectively, then it is little surprise that characteristics judged to be more real are considered more important. Social perceivers and actors are unlikely to base their identities, judgments, or communications on characteristics that they believe to be superficial, flimsy, and subjective. However, we would argue that essentializing a personality characteristic goes beyond adopting a realist view of it. Characteristics could be seen as real underlying causes of behaviors without also being conceptualized as biological, immutable, or discrete. The fact that these beliefs cohere with those that more directly represent the realist view (i.e., inherence, consistency) indicates that essentializing a personality characteristic is not simply treating it as real. Instead, it amounts to treating the characteristic as a real essence. It does seem to be the case that some kinds of personality characteristics are essentialized substantially less than others. Notably, the highly evaluative personality characteristics (Benet-Martínez&Waller, 2002) received very low ratings on the essentialist belief items in both studies. Although undesirable and relatively rare characteristics were generally essentialized less than others, the highly evaluative terms were still essentialized less than the personality disorder descriptors, despite similar perceived deviance. One interpretation of this finding is that the highly evaluative personality terms were judged to be more in the (jaundiced) eye of the beholder than in the person beheld. Thus, these terms, most of which are somewhat abusive, may be seen less as inhering, enduring, consistent, and biologically based features of persons and more as context-specific assessments made by external observers. Although highly evaluative terms may represent important but neglected forms of personality description (Benet-Martínez & Waller, 2002), people appear to perceive them to be quite different in nature from other personality attributes.
Evaluative Implications of Essentialist Beliefs Research and theory have tended to emphasize the dark side of essentialist thinking about difference.
Allport (1954) drew attention to the link between beliefs in a group essence and prejudice, and Rothbart and Taylor (1992) argued that viewing social categories as natural kinds accentuates group differences. Yzerbyt et al. (1997) argued that essentialist beliefs rationalize unjust social arrangements, Levy et al. (1998) demonstrated that “entity theorists” are especially apt to endorse stereotypes, and Haslam et al. (2000) found that devalued social groups tend to be more essentialized than others. Our findings contribute to a growing awareness that essentializing human differences is not invariably negative in its implications. Leyens et al. (2000, 2001) demonstrated that a distinctively human essence is preferentially attributed to favored ingroups, and Castano (2004) showed that people prefer to belong to essentialized ingroups. Haslam et al. (2002) found that some essentialist beliefs were associated with more pro-gay attitudes, and Verkuyten (2003) showed how essentialist discourse can have progressive aspects for members of ethnic minorities. The present study, therefore, adds to a body of work that shows essentialist beliefs to have complicated implications for understanding difference. One possible way to resolve these complexities is to propose that essentialist beliefs have different dynamics and determinants in different domains. It is clear that many stigmatized social categories tend to be essentialized and likely that essentialist beliefs contribute to their devaluation by rationalizing their low status and accentuating their distinctiveness. It now seems equally clear that personality characteristics that are valued and normative tend to be essentialized, and that essentialized characteristics are perceived to be socially important. These conclusions are consistent with Dunning’s (1995) finding that people self-enhance most on traits that they believe to be stable and important. This rather stark difference in the implications of essentialist beliefs may hinge on the kind of nature that is being ascribed to social categories as distinct from personal attributes. Personality characteristics appear to be essentialized to the extent that they partake of human nature. All people can be seen as intelligent or imaginative, at least to some degree. Most social categories, in
contrast, cannot easily be understood as aspects of an encompassing human nature. They are, instead, ways in which some humans are perceived to be categorically different from others. Being female or White cannot be a core aspect of what it is to be human in a world where many people are neither, so whatever nature members of each category share cannot be a broadly humannature. Where social categories are concerned, then, essentialist beliefs may tend to impute a nature that deepens and legitimates a social division and, therefore, have largely negative and exclusive implications.  Where personality characteristics are concerned, however, essentialist beliefs may tend to impute a human nature that is positive and inclusive in its implications.
Essentialized personality characteristics are valued foundations for social identity and judgment. Essentialized social categories, in contrast, are often devalued forms of social distinction. Some limitations of the present studies must also be acknowledged. Although the hypothesized associations between essentializing and social desirability, prevalence, centrality, social importance, and communicability were all large, they are likely to overestimate the associations implicitly perceived by individual participants. Aggregated ratings capture the shared variance in participants’ beliefs about personality characteristics—beliefs that do indeed appear to be reasonably shared and coherent—but do not allow the inference that all participants held the same beliefs with equal strength or a comparable structure. Individual differences in this domain surely exist, and the work of Dweck and colleagues (e.g., Levy et al., 1998) demonstrates their importance. Our studies complement this work by focusing on shared beliefs and on differences among personality characteristics, and they also suggest that individual differences in essentialist beliefs as a whole might well be investigated, and not just beliefs about immutability.
Another limitation concerns our exclusive use of selfratings. Although this is probably unavoidable for assessing essentialist beliefs and simple judgments about personality characteristics (i.e., their desirability, prevalence, and affectivity), the ratings of centrality, relational importance, and communicability in Study 2 may not adequately capture actual tendencies to employ the personality characteristics in identity construction, impression formation, and communication. Future research should examine whether essentialized personality characteristics are preferentially employed when these activities are assessed in more direct and behavioral ways. Ideally, also, future research would develop experimental methods for manipulating essentialist beliefs rather than rely on correlational methods. Despite these limitations, our studies make several potentially important contributions. First, they establish that implicit personality theories make essentialist assumptions about at least some personality characteristics, and that these assumptions have a similar structure to those that are held about some social categories. Second, they indicate that essentialist beliefs are most strongly held about normative personality characteristics, so that positive characteristics are anchored deeply within human nature. By implication, negative characteristics are seen as relatively superficial, inconsistent, and unreal. Finally, our findings imply that essentialist beliefs represent a new, but potentially powerful, determinant of the importance that personality characteristics have in social cognition and communication.

Psychologists have recently begun to examine laypeople’s beliefs about the nature of social categories. A growing body of theory and research indicates that some categories are understood in an “essentialist” manner, such that a fixed, underlying essence is attributed to their members. This essence, whose nature is often only dimly understood, is believed to determine the identity of category members, to render them all fundamentally alike, and to allow many inferences to be drawn about them. Essentialist beliefs have been documented in methodologically diverse studies of ethnicity (Gil-White, 2001), race (Hirschfeld, 1996; Verkuyten, 2003), gender (Mahalingam, 2003), religion (Boyer, 1993), disease (Keil, Levin, Richman, & Gutheil, 1999), and mental
disorder (Haslam & Ernst, 2002).

Several broad conclusions can be drawn from this work. First, essentialist beliefs form a coherent set that captures perceived differences between social categories (Haslam, Rothschild, & Ernst, 2000) and individual differences in perceptions of particular categories (Haslam, Rothschild, & Ernst, 2002). Although theorists often conceptualize the elements of this set differently, these elements include beliefs in the immutability, naturalness, homogeneity, informativeness (inductive potential), inherence, and discreteness of social categories. Second, essentialist thinking is usually theorized to be negative in its implications. Rothbart and Taylor (1992) argued that viewing social categories as essentialized “natural kinds” is a dangerous misapprehension that
accentuates group differences. Allport (1954) described the ascription of essences to outgroups as a basic component of prejudice, and Yzerbyt, Rocher, and Schadron (1997) presented it as a way in which unequal social arrangements are legitimated and naturalized. Essentialist beliefs are associated with some forms of prejudice (Haslam et al., 2002), and Leyens et al. (2000, 2001) have shown that essentialized outgroups are often “infrahumanized,” denied distinctively human emotions that are readily attributed to ingroup members.

Most social psychological research on essentialist beliefs addresses social categories. Personality characteristics — differences between people of a different kind—have been almost completely neglected. At first blush, these characteristics might seem unlikely candidates for essentialist understandings. They are usually understood as personal attributes rather than social identities, represented as adjectival descriptors rather than noun categories, and rarely serve as bases for social organization or discrimination. Nevertheless, personality theorists commonly discuss traits as if they were essences, as
Millon and Davis’s (1996) definition illustrates:
Personality is . . . a complex pattern of deeply embedded psychological characteristics that are largely non-conscious and not easily altered, expressing themselves automatically in almost every facet of functioning. Intrinsic and pervasive, these traits emerge from a complicated matrix of biological dispositions and experiential learnings. (p. 4, italics added) This definition resonates with several of the beliefs identified by writers on psychological essentialism: Personality characteristics are described as deeply rooted and intrinsic, substantially fixed, inductively potent, and at least partly rooted in biological nature. Millon and Davis’s (1996) scientific view of personality is widely shared among trait psychologists. In this view, traits are powerful sources of consistency (crosssituational homogeneity), stability (immutability), and, hence, predictability (informativeness) in behavior. Often these attributes are also understood to have biological underpinnings and to be universal. Proponents of the five-factor model, for example, have distinguished
between these “basic tendencies”—viewed as highly stable, primarily genetic in origin, and largely immune to culture and individual experience—and “characteristic adaptations,” such as values, that are more malleable, contextual, and culturally conditioned (McCrae & Costa, 1999).

Others have framed the same distinction in a plainly essentialist fashion, distinguishing deeply rooted “core” from “surface” attributes (Asendorpf & van Aken, 2003). Indeed, the only essentialist belief that does not feature prominently in scientific conceptions of personality is discreteness, as traits are usually understood as continuous dimensions rather than bounded “types” (Haslam, 2003; Meehl, 1992). This essentialist view of traits has not gone unchallenged, and critiques of trait psychology have a decidedly antiessentialist flavor. The inherence of personality characteristics has been challenged by writers who see traits as mere labels, social constructions, or perceptual categories used to judge others reputationally (Hogan, 1996) or who conceptualize traits as summaries of observable acts rather than as reified latent variables (Buss & Craik, 1983). The consistency (homogeneity) of traits was one target of Mischel’s (1968) situationist critique, which also challenges their predictive power (informativeness). The supposed immutability of personality— the idea that it is “set like plaster”—has been attacked by writers (e.g., Srivastava, John, Gosling, & Potter, 2003) who also take issue with the “biologism” of trait theories.

If the essentialist view of personality has been challenged and defended within academic personality psychology—albeit not by that name—it is unclear
whether similarly essentialist beliefs pervade implicit personality theory. Does the layperson’s folk psychology, that is, construe personality characteristics as immutable, informative, discrete, and biologically based entities that inhere within the person? Research examining this possibility is scarce, because most research on implicit personality theory addresses the covariation structure of personality (e.g., Haslam, Bain, & Neal, 2004) rather
than its ontological status. Several studies partially remedy this neglect. Semin and Krahé (1987) found that lay conceptions of personality operated at more than one tier, drawing inferences between underlying (genotypic) and manifest (phenotypic) levels of understanding. Research by Chiu, Hong, and Dweck (1997) indicates that laypeople hold a view of personality as enduring and latent dispositions (“lay dispositionism”). Levy, Stroessner, and Dweck’s (1998) work on “implicit person theories” shows that people who hold an “entity theory,” in which personality is taken to be fixed, tend to favor biological and intrinsic explanations of stereotype content. They also draw trait-based inferences more rapidly and extensively than their peers in a way that implies a belief that traits are highly informative. Heyman and Gelman (2000a) found that young children hold mixed views on whether traits are innately determined but judge them to be less heritable than physical features. Heyman and Gelman (2000b) also demonstrated that preschool children draw inductive inferences from personality traits in preference to outward appearance and do so much more strongly when these traits are ascribed to people rather than dolls.

All of these studies address aspects of essentialist thinking about personality—particularly inherence, immutability, naturalness, and informativeness or inductive potential—but they do not conceptualize these as elements of a broader essentialist view. Gelman (1992) first drew attention to essentialist assumptions in lay conceptions of personality. Commenting on work by Yuill (1992), which theorizes that people hold a realist view of traits as underlying causal entities rather than mere descriptive labels, Gelman proposed that the realist view corresponds to a belief in essences. Understanding traits as latent causes implies that they have a nonobvious basis and rich inductive potential, which may reflect an extension of a biological view of essences: People very likely transfer some of their  assumptions about biological essences to their ideas about traits. For example, people may assume that traits—like essences—are innate and biologically based. The environmental impact on traits and their context sensitivity may be downplayed; their fixedness may be exaggerated. (p. 284) Gelman (2003) subsequently examined essentialist thinking about personality in a pioneering study in which undergraduates rated 12 characteristics on items assessing a variety of beliefs (e.g., in innate predisposition, genetic basis, biological underpinnings, immutability, universality). Gelman reported consistent differences between characteristics in levels of ascribed essentialism, with “politically conservative” lowest and “schizophrenic” highest, although most mean ratings were in the antiessentialist direction on the scale. These ratings were, therefore, lower than would be expected for racial, ethnic, and gender categories, indicating that personality characteristics are typically essentialized to a moderate extent.

Gelman’s (2003) study represents an important first contribution to this topic, demonstrating that personality attributes are often somewhat essentialized, that different essentialist beliefs cohere, and that some attributes are essentialized more than others. As a first step, it also has some limitations. First, the study does not establish the structure of essentialist beliefs about personality and whether the relevant questionnaire items form a coherent set. Second, the sample of personality characteristics is small. Third, the study does not investigate any factors that might contribute to the differential essentializing of personality characteristics or any correlates or implications of these differences. The studies reported in this article were designed to examine these questions. In two studies, we investigated whether personality characteristics are essentialized in a coherent way and how the structure of essentialist beliefs about personality should be described. Our studies also examine several possible correlates of essentialist beliefs.

Although Brunswik and his students (e.g., 1944, 1947; for a overview, see Hammond, 1980) attempted to address this issue through the development of his  representative design” and “rich stimulus” approaches, these approaches have garnered little support by social psychologists. Perhaps the most serious effort to address the validity issue has been the use of “manipulation checks.” Nevertheless, on those infrequent occasions wherein manipulation checks are used and reported, they are themselves of unknown validity. Moreover, if the results of manipulation checks fail to converge with the primary findings of the study, investigators often assume that the manipulation check was faulty or that the effects of the manipulation were simply inaccessible to participants (e.g., Nisbett & Wilson, 1977). And even if valid manipulation checks were used routinely, they would not fully address the omitted variable problem because they are only capable of revealing what the manipulation did do; they cannot provide assurances that the manipulations’ effects were limited to those intended.
Although the omitted variable problem is not fatal, recognition of this and related problems did dampen some of the enthusiasm enjoyed by advocates of experimental approaches. This problem was further compounded by the recognition of experimentation’s problems with external validity. Difficulties in Establishing the ExternalValidity of Experiments Until the early 1970s, social psychologists were far more concerned with issues related to internal validity than external validity. Instructors of methods classes justified this imbalance by noting that if an experiment lacks internal validity, questions about external validity are moot. The logic underlying the priority placed on establishing the internal validity of experiments has merit, as experiments lacking in internal validity are indeed uninterpretable. Moreover, there surely are instances in which the researchers’ interests do not extend beyond what occurs within the confines of a narrowly defined laboratory setting. In such instances, “in principle” demonstrations are perfectly legitimate and acceptable outcomes of the research process (e.g., Mook, 1983). Nevertheless, Gergen (1973) argued that the results of social psychological experiments may not generalize beyond a particular historical epoch (but see Schlenker, 1974). Others argued that an exclusive focus on the internal validity of experiments encourages researchers to focus on the reality of the contexts that they create in their laboratories to the exclusion of the contexts to which they hope to generalize (e.g., Alexander & Knight, 1971).

Experimentalists may venture down a path where they can only see failed experiments as flawed designs rather than as examples of mistaken hypotheses. Embedded in their self-generated labyrinths of independent and dependent variables, researchers may be seduced into concluding that the only thing that matters is to somehow make the experiment “work,” to forge whatever connections are needed to induce participants to respond as they are “supposed” to respond. Experiments may thus cease serving as vehicles for making discoveries, becoming instead contrivances commandeered by researchers intent on finding what the “theory” knows to be true (e.g., Ickes, 2003; McGuire, 1973). Such concerns were surely disillusioning for advocates of experimentation. This disillusionment, coupled with the fact that personality and individual difference based approaches were much stronger in the external validity department (by virtue of the fact that psychological tests could be administered to relatively large, diverse samples), may have led some researchers to shift from experimentation to personality psychology. The Emerging Symbiosis of Personality and Social Psychology Although our emphasis here has been on the comeback
of personality and individual differences, we should note that social psychology has continued to thrive while this comeback has occurred. Witness, for example, the substantial gains that social psycho