Early Tests of Piagetian Theory Through World War II

Bernard C Beins. The Journal of Genetic Psychology. Volume 177, Issue 6. 2016.

Psychologists recognized the importance of Jean Piaget’s theory from its inception. Within a year of the appearance of his first book translated into English, The Language and Thought of the Child (J. Piaget, 1926), it had been reviewed and welcomed; shortly thereafter, psychologists began testing the tenets of the theory empirically. The author traces the empirical testing of his theory in the 2 decades following publication of his initial book. A review of the published literature through the World War II era reveals that the research resulted in consistent failure to support the theoretical mechanisms that Piaget proposed. Nonetheless, the theory ultimately gained traction to become the bedrock of developmental psychology. Reasons for its persistence may include a possible lack of awareness by psychologists about the lack of empirical support, its breadth and complexity, and a lack of a viable alternate theory. As a result, the theory still exerts influence in psychology even though its dominance has diminished.

It is not an understatement to assert that Jean Piaget contributed more to the study of developmental psychology than any other single individual. His initial work in the 1920s spurred lines of research that still resound today. In fact, Haggbloom et al. (2002) listed him as the fourth most influential psychologist in history, after notables B. F. Skinner, Sigmund Freud, and Albert Bandura, based on journal citation frequency, introductory psychology textbook citation frequency, and survey responses by members of the American Psychological Association.

In some ways, however, it is curious that his impact was so great because, from the start, there was a persistent pattern on the part of subsequent psychologists not to question his theory even when their research failed to confirm his hypotheses. Based on the body of empirical research published between the emergence of Piaget’s initial books and the period around World War II, one can conclude that Piaget’s observations were descriptively sound, if not brilliant, and his methodology innovative, whereas his theory showed questionable elements.

Despite the limited empirical support for important elements of his theory, Piaget’s ideas became the foundation of developmental psychology for decades and still form an important bedrock of developmental psychology. It might be illustrative to briefly note the state of developmental psychology in the early decades of the 20th century as a backdrop to the success of Piaget’s ideas because the impetus of his work to the exclusion of other historical figures is still featured in virtually every introductory and developmental psychology class.

With the inception of Wilhelm Wundt’s laboratory, psychology as a systematic science focused on sensory and perceptual processes of human adults. Because children could not introspect or provide reliable reaction time data, they were largely absent from the discipline. In addition, although one might speculate from the state of the discipline today that psychological theory would have been viewed as an ideal vehicle for application to educational settings, academic psychologists displayed significant resistance to taking it outside the laboratory (Benjamin, 2006).

Nonetheless, attempts at application were probably inevitable given the functionalist point of view that pervaded American psychology a century ago, in addition to the fact that such work could supplement the meager academic salaries of that era (Benjamin, 2006). Furthermore, applications had been part of psychological thought before it became a scientific discipline (Benjamin & Baker, 2004).

It was not until G. Stanley Hall (1893) initiated his pedagogically focused Child Study Movement (CSM) that systematic research with children took hold. His methodology involved use of the syllabus (i.e., questionnaires) to study varied characteristics of students, such as their sense of self, fears, attention, knowledge of facts, and so forth. The results of the research, according to Bradbury (1937), were not useful for applications either in psychology or in education. Nor was Hall’s methodology sound in her opinion. This is not to say that the movement was unimportant, however. As Bradbury pointed out, although the data were of limited value, CSM:

Resulted in (1) an increased recognition of the importance of an empirical study of child psychology and of educational problems in general, (2) a realization of the necessity for a critical evaluation of method, (3) a comprehension of the importance of childhood per se. For the first time the child became the center of psychological and educational thought. (p. 36)

One major criticism of the CSM, aside from its subjective methodology, was its atheoretical approach. Neither Hall nor his students provided a unifying theme for the enterprise, as Hugo Münsterberg (1898) suggested when he opined that pedagogical research had generated merely “odd bits and ends” (p. 166). Of course, psychology was not monolithic even then; some notable psychologists were critical of Münsterberg’s criticisms (e.g., Cattell, 1898).

Although Hall’s approach lacked a theoretical unity, some of his ideas presaged those of Piaget. For example, Hall was a stage theorist, as was Piaget. Hall was impressed by Freud’s stage theory and was comfortable with stages associated with recapitulation theory, but more directly relevant here were Hall’s stages whose chronology aligned quite well with those Piaget would later develop: infancy to two years, childhood to age 8 years, and youth to age 12 years (Bradbury, 1937).

Similarly, the importance of studying children in their own, natural environments gained momentum, with recognition that the content of children’s minds themselves is less important than how children behave and develop within their environments (King, 1903; O’Shea, 1906). King also considered issues of moral development, writing that for very young children, truth is something to be manipulated to match their desires; for older children, it is more external in nature. Both concepts, interaction in the environment and development of morality, augur Piagetian ideas.

Likewise, Baldwin’s (1906) book on the development of mental processes anticipates ideas that Piaget would later develop in greater detail. For instance, Baldwin discussed the ideas of assimilation and accommodation in ways that current readers would recognize as being related to Piaget. In addition, Baldwin invoked change that implies qualitative differences between the young and the old. Further, King anticipated the idea of qualitative differences between child thought and adult thought.

“The mental processes of the child are no longer to be regarded as imperfect affairs. They have all the meaning and the reality that the mental events of the adult have. True, they may not be at all like the adult events but they are entirely legitimate and valid, because they have arisen within a certain type of experience, and they must be interpreted in terms of the experience that rendered their appearance necessary” (King, 1903, p. 8).

Thus, there are early signs that psychologists were interested in developing programs of developmental research and were identifying ideas proposed later by Piaget and eagerly adopted by American psychologists. Even though it was American psychologists who broadened significantly the scope of psychological research around the turn of the 20th century, the importance of developmental and pedagogical research caught on in other countries because of Piaget. For instance, Katzaroff (1935) remarked that prior to Piaget’s so-called clinical method of research, developmental psychology in Bulgaria was in deep crisis (eine tiefe Krise) because the lack of valid, systematic methodologies. And psychologists in India recognized the value of the Piagetian approaches (Gupta, 1947; Menon, 1942, 1944).

As such, with the faltering CSM and no viable replacement, the timing of Piaget’s ideas was favorable. Hall’s functionalist approach involving pedagogy appeared to ignore the study of mental processes or structures (Bradbury, 1937), and the dominant behavioral nature of psychology in the 1920s further diminished the study of mental states (Cantril, 1935), even though there was still interest in cognitive development. Developmental psychology was an area in search of a theory and a methodology. Piaget provided both.

His ideas spread rapidly to the United States even though his work required translation into English as fewer American psychologists needed to study abroad to learn psychology and as non-English-language influences dwindled. The quality of the translations could be problematic, with “clumsiness and confusions and of greater emphases than Piaget makes in French, but also of actual errors, sometimes the exact opposite of what Piaget says” (Isaacs, 1929, p. 607).

Nonetheless, Piaget’s ideas led to the burgeoning of research on the development of thought in children. His output was notable, with the appearance of influential work in a remarkably short span of time: The Language and Thought of the Child (1926), The Child’s Conception of the World (1929), The Child’s Conception of Physical Causality (1930), Judgment and Reasoning in the Child (1928), and The Moral Judgment of the Child (1932).

Regardless of any theoretical shortcomings, psychologists recognized that Piaget had provided fertile ideas for research (Impressions of the International Congress, 1930; Isaacs, 1929). Although psychology has for some decades been in a post-Piagetian era (e.g., Beilin, 1992; Newcombe, 2011, 2013), his name is one of the few from that era that is still invoked as still having direct relevance to scientific psychology. Beilin commented that the number of studies conducted within the Piagetian perspective is “unrivaled” (p. 191). Interestingly, Beilin noted that attacks on the theory have regularly cycled through psychology, with research particularly focused on the so-called Achilles heel of Piagetian theory, the counterintuitive aspects like conservation and formal operations that Beilin suggested had distorted the theory and prevented a full appreciation.

Naturally, trying to encapsulate the complexity of Piagetian ideas briefly is impossible and to test them comprehensively poses great difficulty. In addition, the early research on his theory often focused on individual differences, which Piaget disavowed as part of his perspective. He was interested in a generalized, biological framework that represented the species (Edelstein & Schroeder, 2000), which is inconsistent with the American tradition of standardized methodology and differential psychology. The details of his theory are numerous, and the intertwining of concepts abounds. Consequently, I will limit this discussion to the aspects of the theory that early researchers investigated as they tested Piaget’s ideas. The concepts that received most attention include (a) egocentrism, (b) animism, and (c) the importance of chronological age to stages of development. These domains are, in fact, exactly the ones that Beilin (1992) highlighted as subject to greatest regular investigation. The popularity of these concepts as the focus of research may have been fostered by Piaget’s emphasis on realism, animism, and artificialism. His contribution to Murchison’s (1931) Handbook of Child Psychology provided considerable theoretical detail and numerous examples with respect to these ideas and could have directed researchers toward them.

The sources on which this article is based represent a nearly exhaustive body of English language research with some German sources as listed in PsycINFO with Piaget either in the title of the article or appearing in the abstract.


One of the key developmental concepts advanced by Piaget is egocentrism, the inability to adopt a perspective different from one’s own and a failure to differentiate between one’s own internal reality and objective reality.

Investigators made use of the study of language, morality, and perspective taking (among others) to assess the insights that Piaget developed regarding egocentrism and its manifestations. Reviews of Piaget’s theory generally and egocentrism specifically began to appear in the late 1920s, only a few years after his first book, The Language and Thought of the Child (1926) was published in English. Empirical tests followed shortly thereafter.

According to Piaget, language use provides an indication of egocentric thought that is directed to the child itself. Not until children become more socialized do they recognize that others do not necessarily know the things they know or perceive the word differently than they do.

This issue of the degree to which children can communicate their understanding of the world to others is critical to Piagetian theory. So a failure to verify Piaget’s hypotheses regarding such communication would seem to be quite problematic. As it turned out, a series of published studies investigating different aspects of egocentrism failed to provide much support for Piaget’s ideas.

For example, one testable implication of the egocentrism hypothesis involves seeing whether children can mentally navigate through an imagined space to identify another’s perspective (Inhelder, 1944). Early tests involved whether children could comprehend that their left side is another person’s right side (Lane & Kinder, 1939; Menon, 1944). A later, related incarnation of such a test is the so-called “three-mountain problem” in which children attempt to describe what another viewer would see from a different location (Cox, 1975; Garner & Plant, 1972).

Menon (1944) quizzed a group of Indian children 7-9 years old on their perceptions of right and left with respect to the child and to another person. With the experimenter opposite the child and holding a coin and a book, Menon posed this question: “You see this anna [a coin]. Have I got it in my right hand or in my left? And the book?” (p. 88). Such questions led to successful responses between 75% and 98% of the time, depending on the particular test. As Menon pointed out, not only did the results not support Piaget’s hypothesis, the Indian children and Piaget’s Swiss children did not show the same pattern of improved performance on the various tests that were of differing levels of difficulty.

Furthermore, Menon (1944) tested the children’s reasoning on brother-sister questions such as this: “Manian has three brothers-Srinivasam, Jayaram, and Rangan. How many brothers has Srinivasam? And Jayaram? And Rangan?” Once again, these children showed little evidence of egocentrism, solving an average of 85% or higher on each of the questions. Menon’s conclusion was that the data “do not agree on the whole or in their details, with those of Piaget” (p. 90). That is, children are capable of engaging in relational thought, reflecting an awareness of a reality outside themselves.

In a longitudinal case study, Dennis (1942) followed his daughter’s development through her first six years. He reported that she engaged in magical thought (e.g., “she could control the rain by saying rain, rain, go away”) as expected, and she showed the sequence of developments that the theory postulated. But the chronology of development of adult-like logic did not conform to Piaget’s ideas. His daughter was significantly advanced relative to theoretical expectations, which has implications for the assessing stage-like development, which is discussed subsequently.

Another implication of egocentrism is that children do not attempt to explain themselves to others or possess the ability to do so (Abel, 1932). Furthermore, in the early stages of development, children are thought not to be able to understand logical relations beyond their own immediate apprehension. This hypothesis suggests that development of a child’s social nature requires movement past the stage of egocentrism. Such movement is a function of chronological age in Piaget’s view. According to theory, young children show notable egocentrism until around 6-8 years old. Perusal of virtually any psychological description of young children reveals this stage as a standard concept. Problems regarding this hypothesis appeared from the start, however. Becker (1933) pointed out that in his research, even young children asked for explanations of things they did not understand.

Johnson and Josey (1931) were among the first psychologists to examine Piaget’s hypothesis regarding the idea that young children cannot engage in true social speech or to adopt the perspective of another person. Although they did not provide detail regarding their methodology other than noting that they used the same tests that Piaget had developed, Johnson and Josey reported greater problem solving and logical ability than Piaget’s children, asserting that they were “socially minded, could assume the position of another and even that of an hypothesis” (pp. 338-339). Further, they were eager to make themselves understood. In addition, Hazlitt (1930) reported that children supposedly in an egocentric stage were able to generalize their understanding of a concept to a new situation. Subsequently, Welch and Long (1943) reported similar findings of little difference in reasoning in children 3-5 years old compared to slightly older children, although younger children had more difficulty generalizing from early problems to later, related problems.

Interestingly, Johnson and Josey (1931) did not specifically question Piaget’s theory. Rather, they suggested that differences in intelligence among the groups of children may have led to different outcomes. They also speculated egocentrically that “perhaps the English language is superior to the French as an instrument for logical thinking” (Johnson and Josey, 1931, p. 339).

Another, later test of the egocentricity hypothesis involved a comparison of twins and singletons in their use of language (Day, 1932). This published work was based on earlier, unpublished research conducted at the University of Minnesota in 1930 that had invoked Piaget’s system of language analysis. Day hypothesized that the children whom she observed (2-5 years old) would emit egocentric speech involving Piaget’s categories of repetition, monologues, or dual monologues rather than socialized speech identified as adapted (e.g., remarking about the situation) or critical (e.g., asking questions). Her results revealed little evidence of egocentric speech even among three year olds and not much even with the younger children.

Day’s (1932) research focused on differences between singletons and twins. She found that at the youngest age (2 years old), twins showed notably more egocentric speech than singletons, but even then, a large majority of utterances were not egocentric.

Another aspect of egocentrism entails children’s use of logic to reason through problems. Menon (1942) used Burt’s (1922) Reasoning Test, which posed such questions as “What would you do if you missed a train?” Menon (1944) did not specify the specific questions used in the research, but Burt cited this example as appropriate for a child 9 years old. As with Menon’s work on the left-right and brother-sister problems, the results on the reasoning test showed that young children were capable of reasoning through problems. The juxtaposition (i.e., mere concatenation of statements without logical progression) that Piaget suggested would appear was not in evidence.

Similarly, in a study of children’s notions of causality, Gupta (1947) discovered little evidence of egocentricity in children 6-8 years old. When their statements showed logical gaps, Gupta opined, it was not due to egocentrism. Rather, a child might have omitted some elements of the train of logic for the same reasons that adults do; they may not realize that a particular element has to be conveyed in order for complete understanding of their point. As Gupta stated, “In ordinary speech, even adults do not state all premises and deduce or induce logically from them. They just take it for granted that any people or ordinary common-sense will understand the rest” (p. 53). It is through socialization and experience that the child gains awareness of the need for full and complete understanding; logical awareness, according to Gupta, is inborn, but its practice is acquired. In addition, as King (1903) had earlier implied and Vinacke (1951) later argued, what an adult views as illogical may be perfectly logical from the child’s perspective.

The importance of language ability comes across in the writing of different investigators. Not only might a child’s expressive ability be a limiting factor in problem solving, but the wording of the problem may be the issue. In testing children’s reasoning, Müller (1932) adapted the wording when a child failed to respond correctly, at which point the children were often able to solve the problem. Two decades later, Nass (1956) raised the same point, although he did not cite Müller’s work, which had appeared in a German journal.

In a somewhat unusual twist in the research on egocentrism, Abel (1932) created a setting in which adults would be relatively untutored in a subject to be discussed. The researcher read brief passages to adult college students who then repeated what they had heard. In the next step, the college student explained to another student what she had heard. According to Piaget, egocentric children repeat less than they comprehended; in Abel’s research, the students engaged in such a pattern. Furthermore, when the students tried to explain the passage to a second student, they showed the same limitations as did children in similar circumstances.

Abel (1932) pointed out that Piaget recognized that adults would show behavior that appeared egocentric in complex or stressful situations. But she noted that the college students showed the same type of logical missteps that children did in Piaget’s experiments. As such, she concluded that children’s failings in reproducing and explaining what they know may not reflect egocentrism; rather, such failures may be aspects of normal memorial processes regardless of developmental level.

So what are the implications for acceptance of Piagetian ideas regarding his descriptions of egocentrism and the development of logical relations? It appears that as extensive as Piaget’s research and writing were, the details of the theory required revision if the research findings of subsequent investigators were valid.

The empirical psychologists had come to recognize that young children’s thought was different from that of older children and adults. There was no disagreement on that count. In addition, psychologists recognized the strengths of Piaget’s methodologies even when they could not reproduce Piaget’s findings with respect to the logical, linguistic, and social competence of young children who were supposedly locked in an egocentric stage of thought.

As Isaacs (1929) asserted a mere three years after Piaget’s initial work had appeared in English, there had been no greater figure in developmental psychology than Piaget. Hazlitt (1930) reinforced this idea when she noted that Piaget’s ideas, particularly those on egocentrism, were among the most interesting and important to have appeared in recent years. Thus, from the start, Piaget was having significant impact on the course of developmental psychology.


The second major focus of research on Piaget’s theory revolved around animism, the attribution of life to inanimate objects. Piaget reported that young children attributed life to nonliving objects, particularly when movement was involved.

Unlike the conceptualization of egocentrism that Piaget advanced, animism was not a new concept. Dennis (1938) commented that the idea existed in classical times when Zenophanes supposedly wrote that “if horses and oxen thought in the human manner, they would imagine gods in the forms of horses and oxen” (p. 258). Various philosophic sources (e.g., Hume, 1889) had recognized the fact of animistic thinking both in children and in adults, as had psychologists (e.g., Slaughter, 1913). In fact, Dietrich Tiedemann had systematically studied his own child in 1787 and reported animistic thought in what Murchison and Langer (1927) cited as the first scientific study of the behavior of young children (Beobachtungen über die Entwickelung der Seelenfähigkeiten bei Kindern). Piaget had not drawn from many sources in his discussions of animistic thought so, according to Dennis, was not conversant with some contemporary psychological thought in this area. Further, Piaget seemed to have believed that animism was largely limited to children. So Piaget’s thoughts on animism bypassed ideas that had already appeared.

Nonetheless, Piaget’s timing was propitious in that there existed a vacuum with respect to developing knowledge of the structure of children’s thought. As Dennis (1938) argued, laboratory psychology had abandoned the study of the nature of child thought in favor of the content of child thought. Hall’s (1893) research, which was essentially the standard for developmental research, involved itself largely in issues of children’s preparedness for school and their knowledge of the world. In contrast, the process of children’s thinking received little attention.

According to Piaget, children progress through four stages regarding animistic beliefs: (a) all functioning objects (e.g., those that are not broken) are alive; (b) objects that move (e.g., clouds) are alive; (c) things that move under their own volition are alive; and (d) animals, and maybe plants, are alive (Bruce, 1941).

In what appears to be the first published assessment of Piaget’s ideas on animistic thought, Huang (1930) studied children’s responses to so-called strange phenomena (i.e., magic tricks) to see how they would explain outcomes that were so discrepant from expectations.

The children in Huang’s study showed little evidence of animistic thought. In fact, Huang reported little egocentric thought on the part of the children, who were 4-9 years old, reporting that, although they had difficulty synthesizing and integrating information, the children used a logical and naturalistic approach to explaining the illusions, presaging later work (e.g., Welch & Long, 1943). Huang suggested that Piaget may have seen animistic thought because the subjects of the children’s statements (e.g., clouds) were often the focus of myths and stories, a point that Slaughter (1913) had discussed in describing children’s conceptualizations of the moon.

Subsequent investigations were mixed regarding support for the theory, although the negative outcomes outnumbered supporting data. Johnson and Josey (1931) claimed broadly that the children they examined showed no animism at 6 years old; in fact, they asserted that children of that age displayed little egocentrism or artificialism.

In contrast, Russell and Dennis (1939) developed a standardized method for studying animism that produced reliable results that replicated Piaget’s findings to a degree. In a series of studies, Russell (1940a, 1940b) and Russell, Dennis, & Ash (1940) replicated the finding that the children he tested did progress through the stages that Piaget had postulated and in the order that Piaget specified. At the same time, he noted that there is not a clear delineation by age across the stages. Russell (1940a) stated that different children at a given age were at varied stages of development with respect to animism. And when he re-tested a group of children, some had moved forward in their development, whereas others had regressed. Beyond this, Russell et al. (1940) stated that mental age was more predictive of movement through the stages of animism than was chronological age.

Further failures to support Piaget’s theoretical mechanisms regarding animism appeared in Russell’s (1940b) report on children’s conceptualization of whether objects showed consciousness and awareness. He noted that Piaget had hypothesized that development of such concepts should follow the same path as those specifically of animistic thought. Russell’s data did not support the hypothesis. In some cases, children’s conceptualizations of what is alive versus what is conscious developed in an order reverse of that posed by the theory.

Meanwhile, in reviewing a book by Deutsche, The Development of Children’s Concepts of Causal Relations (1937), McCarty (1938), recalled Deutsche’s empirical finding that if animistic thought occurred in children, it had disappeared by 8 years old. In fact, Deutsche had claimed that animistic responses to questions were conspicuous by their absence.

Granich (1940) also reported evidence of animism in younger, developmentally disabled children, although it was exceedingly rare for children to report that objects that were alive had feelings or could talk. Granich also suggested that Piaget’s categories of animism were insufficient to capture the range of responses in his study. One of his conclusions about the responses of the children was that limitations in language proficiency are such that children’s statements may not reflect their thought processes, anticipating Gupta’s (1947) research findings and reinforcing Müller’s (1932) previous conclusion that changes in wording may allow a child to solve a problem successfully.

With the emergence of these empirical findings, it became clear that children displayed animism in some cases, but there was not overwhelming support for the mechanisms that Piaget hypothesized regarding animistic thought. The types of animistic thought that Piaget identified seemed to be reliable (Russell & Dennis, 1939), although children’s ages, experience with varied concepts, and mental development played a role. Further limitations regarding the theory, as discussed below, include the fact that although Piaget’s belief that chronological age played the dominant role in the evolution of children’s thought, the data reflected the importance of mental age as well (e.g., Granich, 1940).

Naturally, it would make little sense to claim that Piaget was unaware of individual differences in development based on factors like culture or type of interaction with adults (e.g., Lerner, 1937). In fact, Piaget averred that he was not interested in individual differences; rather, he considered general principles (Edelstein & Schroeder, 2000). As such, Piaget would not have been terribly concerned that the American approach of standardized methodology did not support his ideas. And as Abel (1932) pointed out, Piaget recognized that adults could show childlike thought in some situations. So one should avoid simplifying Piaget’s ideas in a way that ignores that complexity of thought structures, a point clearly made by Beilin (1992).

In addition, even the early investigators were reliant on translations of Piaget’s work into English. Such translations were sometimes problematic and characterized concepts in ways opposite to Piaget’s actual ideas (Isaacs, 1929), so researchers may have been basing their research on misconceptions regarding Piaget’s ideas when they claimed that their results were discrepant with Piaget’s theory. Nonetheless, the wide array of such findings strongly suggests that (as one would expect), the nascent theory required further refinement.

Ages and Stages of Development

Piaget posited that child thought progresses toward adult forms of logic through a series of well-defined stages. As noted previously, one such stage was egocentrism. According to the theory, children would display specific characteristics of thought at specific ages. That is, chronological age per se was associated with certain capabilities.

As psychologists examined child thought from within a Piagetian framework, the results were again mixed with respect to support for the theory, just as they were in assessments of egocentrism and animistic thought. Typically, early investigators examined the phenomena described by Piaget (e.g., how children responded to a query as to whether a particular object was alive), then applied the findings to considerations of stages as a theoretical concept.

Once again, it is important to recognize the complexity of the issues. Development does not proceed identically across people. So if a particular research result failed to support Piaget’s ideas, it could be that the investigator was viewing Piaget’s theoretical statements too narrowly. On the other hand, a relevant question involves how far a set of research results can depart from theoretical expectations before one concludes that theoretical mechanisms are problematic. In consideration of the existence of theoretical stages, there are more complexities than in the consideration of specific, overt behaviors.

Tests of egocentric thought sometimes led to support of the theory. For example, Conn (1948) documented the type of egocentric thought predicted of young children, this time in the context of where babies came from, and Zietz (1939) expressed support in children’s movement toward adult-like logic around 10-14 years old, although they did not set out specifically to test the theory. However, the clear majority of attempts at replication failed (e.g., Johnson & Josey, 1931; Lane & Kinder, 1939; Menon, 1942, 1944; Dennis, 1942; Müller, 1932). Children simply did not appear to systematically engage in the type of egocentric thought associated with different developmental stages.

One common result regarding children’s progress toward adult thought was that it tended to appear at an earlier age than hypothesized. For example, Johnson and Josey (1931) tested 6-year-old children for problem-solving abilities and reported consistently nonegocentric thought. What might account for such discrepant results? Several investigators suggested that language was important. That is, children’s expressive ability and comprehension may have distorted the appearance of their thought processes (Granich, 1940; Welch & Long, 1943). Given the apparent importance of intelligence level (i.e., IQ score) in reasoning (e.g., Johnson & Josey, 1931), the speculation of the importance of language seems quite reasonable.

Another speculation involved the children’s environment. For example, Becker (1933) reported children from religious backgrounds tended to show more magical thought than did children from other environments. Abel (1941) showed that developmentally disabled, institutionalized girls showed different levels of moralistic reasoning about punishment than such girls living in the community. She found that institutionalized girls engaged in moralistic reasoning more than the other girls. That is, institutionalized girls tended to view an act with a negative outcome as meriting punishment without regarding the intent of the action. Thus, somebody who is trying to help but causes a negative result was seen as deserving of punishment to the same degree as somebody who deliberately caused a problem.

Abel (1941) reasoned that girls in institutions lived in an environment in which punishment was a regular feature of their lives, regardless of the intent of the actions; girls in the community were less likely to experience that pattern. Further, Abel pointed out that so-called recalcitrant girls in institutions were more advanced in their moral reasoning, suggesting a significant role of personality in such judgments. In the end, chronological age was less important than mental age in predicting the level of moral reasoning; one cannot ignore either environmental or personality factors. The same potential limitations exist in Dennis’s (1942) longitudinal study of his daughter in a natural environment.

The failure to replicate the order in which thought develops posed another problem regarding Piaget’s stage hypotheses about child thought. For example, Menon’s (1944) children showed a different order of development of stages in egocentric thought compared to Piaget’s, as did Russell’s (1940b) regarding animistic thought. Relatedly, Russell (1940a) and Bruce (1941) both revealed that at any given chronological age, different children showed different stages of development of animistic thought.

Thus, with tests of egocentric and animistic thought, research often supported the phenomena that Piaget described. Russell and colleagues (Russell, 1940a, 1940b; Russell & Dennis, 1939; Russell et al., 1940) reported that children showed the types of animistic thought that Piaget hypothesized in the order that he had predicted. Bruce (1941) also replicated the behaviors that Piaget described. However, both Russell and Bruce commented that the progression of thought did not conform to Piaget’s stages. Thus, the phenomena of animistic thought emerged in many children, but the data did not support the proposed, underlying stages.

The Importance of Piaget’s Theory

The difficulty with creating and testing a theory is that theories are always simpler than the reality that they attempt to portray. So failures to support Piaget’s theory may reflect methodologies that do not align with the specific nature of Piaget’s hypotheses. Or the investigations may not have been directed at what are critical aspects of the theory. Piaget’s theory is obviously multifaceted, so extensive testing would be necessary to examine it to lead to acceptance or rejection. In addition, Piaget was not interested in questions of individual differences, so he was not terribly bothered by departures from his theory when those departures were associated with environmental or personal characteristics (Edelstein & Schroeder, 2000).

As I have pointed out, however, the majority of the published research into the World War II era consistently failed to support the theoretical structure even if investigators did document specific behaviors that Piaget described. Psychologists repeatedly noted their inability to replicate Piaget, but nonetheless recognized the power of his ideas. For instance, after failing to support the theory with respect to egocentrism, Huang (1930) said, “we do not mean to imply thereby the validity of Piaget’s conclusions, inasmuch as absence of evidence is not evidence to the contrary” (p. 178). Thus, Huang recognized that one failure does not invalidate an entire theoretical framework and implied that Piagetian ideas provided a useful tool for studying and understanding children. Similarly, Hazlitt (1930) echoed Huang when she said that “One of the most interesting and important works on child psychology that have appeared during the last few years is that of Piaget on the language and thought of the child” (p. 354) while failing to lend empirical support to his ideas.

McCarty (1938) was harsher in her statements about Piaget’s theory: “Thus is added to the American child psychology literature one more well-executed experimental study, which was stimulated by Piaget’s work, but which resulted in conclusions directly opposed to his claims” (p. 475). Even so, Piaget continued to be the reference point about which empirical research revolved.

The failures of the theory echoed across time. Harrower (1934) noted that his studies make sense only within a Piagetian framework, even though he later expressed harsh sentiment about the viability of the theory. Lane and Kinder (1939) subsequently asserted that, despite empirical failings, researchers were paying homage to his theory, a “tribute to the originality and insight of his thinking” (p. 108). Somewhat later, Bruce (1941) questioned Piaget’s ideas on animistic thought, suggesting that such thought gradually evolves but not in discrete stages. Embedded in her conclusions, however, is a recognition that research is meaningfully conducted within a Piagetian framework. Such sentiments recur in many of the failed attempts to support the theory. And throughout the period through the second world war, other researchers also posed their questions in Piagetian terms, failed to support the theory, but nonetheless recognized that Piaget’s ideas were useful in explaining the development of children’s thought.

So what accounted for the acceptance and dominance of the theory for over half a century after its inception?

The short answer seems to be that there was a vacuum in developmental theory and research that needed to be filled. In identifying dimensions of egocentric thought, animistic thinking, moral reasoning, and prelogical thought, Piaget captured behaviors that investigators recognized in children. What was needed was a framework to explain the progression of childlike thought toward adult thought. Piaget’s speculations provided the remedy to the problem.

As I noted previously, the early years of psychological research were not a fertile period for developmental research. Tulchin (1926) reported that, historically, child study attained sporadic attention, but it was not until Lightner Witmer’s 1896 psychological clinic and G. Stanley Hall’s CSM were initiated that childhood became the subject of psychological study.

Witmer focused on applied psychology from an educational perspective using a clinical method (Resnick, 1997). Here, clinical refers to a methodology rather than a location, just as Piaget adopted the term two decades later. But Witmer’s approach did not lead to widespread, systematic research on developmental issues.

Stanley Hall’s CSM, on the other hand, initiated a program of research on children. However, it was more practical than theoretical, just as Witmer’s work turned out to be, focusing largely on children’s preparedness for school. Bradbury (1937) argued that “The net result in terms of actual findings was not important for either psychology or education” (p. 36), pointing out that the work was criticized as being systematically problematic and without a solid theoretical foundation.

By the 1920s, developmental psychologists had no clear home until Piaget’s ideas emerged. Katzaroff (1935) noted that developmental psychology was in crisis because, prior to Piaget’s approach, there was no unifying set of ideas and no methodology that would lead to the emergence of theoretical explanations about childhood. One of the earliest reviewers of Piaget’s initial work stressed that “the value of his approach lies not only in the fresh insight afforded into the child’s speech from the child’s own point of view but in making possible controlled experimentation on more significant data than would have been possible without the preliminary descriptive studies” (Lynd, 1927, p. 278). Schoen (1933) subsequently asserted that Piaget’s later book on moral judgments was yet the most significant of the series of Piaget’s books implying a growing strength of Piaget’s ideas.

In addition, it appears that psychology was still looking for a unified perspective that might provide explanatory power about human thought and behavior in general that went beyond a simple behavioristic approach. For example, in Cantril’s (1935) review of Goodenough’s (1934) book Developmental Psychology, he rebuked Goodenough for too much emphasis on the what of behavior rather than on the why of behavior, neglecting the development of thought.

Piagetian ideas also rippled beyond the realm of developmental psychology specifically. De Saussure (1934) linked Freud with Piaget. Even though the two theorists studied unconscious and conscious thought, respectively, de Saussure argued that the two were actually thinking in concert. That is, Freud stated that people project internal symbols onto an external object, and Piaget argued that children do not distinguish between their internal and external worlds. Thus, the two theories have an element in common that might not be apparent at first glance. He further suggested that mentally ill patients are indistinguishable from children in their thought processes when patients project onto external objects.

And at least a subset of contemporary psychologists at the International Congress of Psychology in 1929 also believed that there was too much emphasis on technology and methodology, but too little on hypothesis and theory. One unnamed writer commented on the significant contributions of Piaget (and Bühler), Thorndike, Lashley, McDougall, and Pavlov as having provided fertile ideas for psychological thought (Impressions of the International Congress, 1930). Relatedly, psychiatrists interested in the Rorschach Test also named Piaget as a significant figure in psychology, along with Freud, Jung, Lewin, Stern, and Rorschach, asserting that in a century these figures would still be recognized as having provided basic growth to the discipline (Shall the Rorschach, 1939). Interestingly, Piaget is the sole individual in these lists whose speculations are still viable in psychological research and discussions rather than simply as historical contributors (Impressions of the International Congress, 1930).

As welcomed as Piaget’s framework was, with such a discrepancy between theoretical predictions and empirical results, it is surprising that the theory gained the significant traction it did. And one might wonder why other investigators did not pose any theoretical alternatives.

Psychologists may simply have recognized the strengths of the Piagetian perspective in thinking about childhood thought. Several contemporary investigators remarked on the importance of the framework. So individual failures to support small aspects of Piaget’s hypotheses in research projects may not have been compelling. For example, with the theory’s complexity, one might argue that the research on moral reasoning by Abel (1941) tapped into different aspects of moral reasoning than Piaget intended. Or one might argue that although the nature of Abel’s tests of reasoning with developmentally disabled girls appears to be consistent with those of Piaget, given the multifaceted nature of reasoning, failures to replicate might reflect methodological or sampling issues rather than substantive issues, particularly given that moral reasoning does not involve a single dimension of thought (MacRae, 1954). Similarly, Granich’s (1940) work with the reasoning of developmentally disabled children may have been a poor test of what is a complex theory. Again, the stimuli and approach that he used appear to be like those Piaget used, but his sample was also clearly different than Piaget’s. Furthermore, if psychologists accepted Piaget’s viewpoint that the theory was a generalized depiction of human development, the discrepancies could be minimized as instances of differential psychology, which was not the point of the theory.

There is no doubt that the psychologists of that time recognized the power of Piaget’s ideas. However, in addition to such power, there was no theoretical competition, although had Lev Vygotsky’s untimely death in 1934 not occurred, perhaps the two theories would have rivaled one another.

Another possibility for the persistence of Piagetian theory, in addition to its potentially broad explanatory framework, is that the failures to support the theory were often unknown. Taking Day’s (1932) research on language development in singletons and twins as an example, it is possible that not many people were aware of her results. Perhaps because a major focus in Day’s (1932) research was on the difference between singletons and twins, with more or less passing reference to Piaget’s theory, psychologists who would have been interested in the theory might simply have overlooked the study. In fact, as reported in PsycINFO, there was not a single subsequent citation of Day’s research by subsequent investigators.

Further, the era of easy access to information had not emerged, although Psychological Abstracts, the forerunner of PsycINFO, first appeared in 1927. As such, the extent to which psychologists accessed research relevant to their own is unknown. Interestingly, during the period of World War II, Inhelder (1944) was still explaining Piagetian methodology to German-speaking audiences even though it had been on record for nearly two decades, suggesting that the ideas were still not completely widespread.

Some studies had received exposure. For instance, since their publication and up to today, Abel’s (1932, 1941) research was cited by several other researchers (13 and 12, respectively); and Dennis’s (1942) longitudinal study of his daughter’s development and Hazlitt’s (1930) work were cited (13 and 27 times, respectively). But other work passed into obscurity almost instantly. The publications by Gupta (1947) and Menon (1942) have not been cited, perhaps because they were in Indian journals; the works by Müller (1932), de Saussure (1934), Zietz (1939), and Inhelder (1944), published in German, were not cited. Other studies were cited only a few times. Thus, psychologists may have been influenced by the strength and complexity of the theory but unaware of its limitations.

In addition, the surge in behaviorism in the discipline may have led psychologists away from the cognitive approaches inherent in Piaget’s work. That behavioral mode persisted into the 1950s and 1960s, at which time both cognitive psychology and Piagetian ideas began to gain traction once again. The dissatisfaction in that era for simplistic behavioral explanations may have provided an atmosphere conducive to acceptance of Piaget’s cognitive approach. As Kessen (1996) demonstrated, citations of Piaget began skyrocketing in the early 1960s, continuing into the late 1970s. Part of the reawakening to Piaget’s ideas may also have arisen due, in part, to Flavell’s (1963) exposition of Piagetian ideas. Flavell’s volume was the first attempt to present an “integrated overview…sufficiently detailed to do justice to the complexity of his theory” (p. 1).

The types of investigations attacking Piaget’s work in the first two decades after it initially appeared seem to constitute the start of a trend that has persisted (Beilin, 1992). Not surprisingly, as knowledge of developmental issues and phenomena has increased across the decades, change in the theoretical structure was inevitable. Psychology is currently in what has been termed a post-Piagetian phase in which the mechanisms and cognitive structures that Piaget posited have shifted. Although psychologists still recognize the importance of Piaget’s theoretical framework, current thinking has moved in new directions (Newcombe, 2011, 2013).

Nonetheless, the power of Piaget’s ideas, including almost immediate translations of his books into English, gave them a weight that could not be overcome with individual empirical studies, many of which went unknown. Consequently, with the vacuum that needed to be filled in psychology, the coherent and complex set of ideas focusing on the species rather than on the individual, the lack of competing theoretical frameworks, and the relative obscurity of research that poked holes in the theory, Piaget’s work came to dominate the developmental landscape for over half a century, with residual power that persists today.