Originally published in Objectivity (1993), Vol. 1, No. 6

Copyright ©1994 by Paul Vanderveen. All rights reserved.

Formation of the Concept of Mind

Paul Vanderveen

What is it that young children know about the mind, and what is the difference between their concepts and beliefs and those of adolescents and adults? What developmental path leads most children eventually to the adult concept of mind?

The formation of the concept of mind may be placed in developmental perspective by drawing upon scientific research findings regarding children's cognitive development and upon philosophical analyses of conceptual cognition. My plan is as follows: initially, to review some recent scientific research regarding the concepts and beliefs of young children; next, to cite evidence in both science and philosophy of a long-standing and widely accepted assumption--namely, that one learns to think in terms of one's mind through an inwardly directed cognitive process; then, to argue against this assumption on epistemological grounds; and finally, with all the foregoing as background and drawing on further scientific research, to outline the developmental path leading a child to the explicit formation of the concept of mind.

Through this process, I establish and then illustrate two crucial points. First, forming concepts of thinking, remembering, dreaming, and similar actions does not necessarily entail identifying them as mental processes. The failure to distinguish between conceptualizing these actions and identifying them as mental is evident in some theorizing of scientists and has led to exaggerated claims about the knowledge of young children. Second, although no one directly experiences more than one mind, conceptualizing minds requires the cognitive integration of two or more--that is, one's own and other minds. Showing the complex manner in which a person accomplishes this cognitive integration of self and others is my chief purpose in this article.

I. The Young Child

Piaget's findings about young children's knowledge of their own experiences stimulated a recent burgeoning of scientific research and debate regarding childhood "theories of mind." While recognizing that young children use words such as believe, dream, and think, Piaget held that children have a limited comprehension of the differences between thoughts and their objects (1929, 37-60). Failing to differentiate "between the psychical and the physical," young children consider thought "a kind of voice" and dreams "little material tableaux which you contemplate in your bedroom" (Piaget and Inhelder 1969, 110). He held that, "from the intellectual point of view," young children do not distinguish "between external and internal, subjective and objective" (1965, 92). They know "nothing of the nature of thought," remaining unconscious of the duality between things and thought, between "a reality that is perceived and a thought that interprets it" (Piaget 1929, 37, 43).

Studies by Laurendeau and Pinard (1962) and Broughton (1978) provided some support for Piaget's view, although Laurendeau and Pinard noted that the children they studied regarded dreaming as interior, personal, and immaterial "at a much earlier age than Piaget's observations would have led us to predict" (1962, 124, 127). More recent research has purported to show that Laurendeau and Pinard also underestimated the capabilities of young children (Estes, Wellman, and Woolley 1989). Reviewing representative research studies in some detail will elucidate what young children think and believe, as well as demonstrate how scientific research is advancing our knowledge in this area. It will also illustrate a significant potential pitfall in characterizing children's conceptual systems. The tension between Piaget's and more recent views is only partially genuine. It also expresses an ambiguity which can arise, given the hierarchical nature of conceptual knowledge, when one uses an adult conceptual system to describe the child's experience.

Estes, Wellman, and Woolley conducted a series of experiments to determine whether preschool children "make a fundamentally correct distinction between mental and physical phenomena" (1989, 42). Their experiments elicited young children's judgments about different items which adults might classify as mental entities (e.g., a thought, dream, memory), real external objects (e.g., a cup, deflated balloon), absent real objects (e.g., the balloon hidden under a box), insubstantial objects (e.g., air, smoke) and physical representations (e.g., a drawing, photograph). Estes, Wellman, and Woolley regarded items in the last two categories as "close imposters" which young children might plausibly be thought, in keeping with Piaget's views, to confuse with mental entities.

The investigators showed line drawings to children, age 3 to 5, and told them brief stories involving 18 mental entities, real external objects, or close imposters--for instance, a story about dreaming: "See this boy. He always wanted a bicycle. Sometimes when he is asleep, he dreams about a bicycle." The investigators then asked questions such as: "Now that this boy is dreaming about a bicycle can he touch that bicycle with his hands?"--and, to elicit reasons for the answers: "Why can/can't he touch it with his hands?" They asked whether the boy (in this story) could see the bicycle with his eyes and whether he could hide it under his bed. They analyzed both the children's answers to the initial questions whether the depicted child could see, touch, or hide the items and the children's explanations for their answers.

The children tended to use distinctively different patterns of explanation regarding the real external objects, mental entities, and close imposters. Half the 3-year-olds, 80% of the 4-year-olds, and all of the 5-year-olds provided what the investigators called mental explanations for their judgments regarding the mental entities, while only a very few of the 3-year-olds and none of the 4- and 5-year-olds did so for the close imposters. Mental explanations included "'Cause it's her imagination," "Because he's just remembering it in his brain," "'Cause it's in his mind," "Because it's in his head," and "'Cause he's just thinking about it."

The investigators next asked preschool children a series of questions about real objects, real hidden objects, and mental images. They showed children a deflated balloon, for instance, and then hid it under a box on the floor, or they showed the children the balloon and then asked them to close their eyes and make a "picture of it in your head." The investigators then asked questions about the visible balloon on the table, the one hidden under the box, and "that balloon in your head"--"Can you see it with your eyes?" "Can you touch it with your hands?" "Can I see it with my eyes?" "Just by thinking about it, can you make it stretch out long and skinny?" They also conducted a final experiment in which they questioned children about "a picture in your head" of a cup and also of a pencil, as well as photographs of these same items.

The children exhibited the adult pattern of responses by the age of 5. They recognized, for instance, that they could touch only the balloon on the table and that they could make neither the one on the table nor the one hidden under the box "stretch out long and skinny" just by thinking about it, but could transform the balloons in their heads that way. A significant minority responded affirmatively when asked whether, with their eyes, they could see "that balloon in your head." These responses were apparently due to "the quasi-visual nature of the experience" (ibid., 77). But when the investigator inquired "Can I see it with my eyes?," the children made the correct response. Informative explanations included a 3-year-old's, "No, but you could see a cup in your head," and a 4-year-old's, "No, because it's only in my head, but you could make it in your head" (ibid., 75).

Clearly, the children distinguished between a real cup and a picture of it "in your head," between a real bicycle and a dream bicycle, knowing that one cannot touch a dream bicycle and ride away on it, except in one's dreams. A 4-year-old explained that a boy dreaming about a bicycle "could touch it with his mind hands" (ibid., 55). Children made other idiosyncratic uses of language to mark known distinctions. As Estes, Wellman, and Woolley commented, Piaget's claim that the child cannot distinguish a real house "from the concept or mental image or name of the house" (Piaget 1929, 55) "seems an overstatement" (Estes, Wellman, and Woolley 1989, 48). The young child does know something "of the nature of thought."

It appears, however, that Estes, Wellman, and Woolley also concluded with overstatements. They claimed that "preschoolers frequently have an explicit, articulate understanding of mental phenomena" and "a solid and articulate understanding of the fundamental differences between mental entities and physical objects" (ibid., 77, 86). In using such language to describe what preschoolers understand and in further characterizing the subjects' explanations as "cogent," "elaborate," and "adult-like" (ibid., 77), they appear to have imputed considerable sophistication to young children. With respect to physical objects, Carey and her colleagues were able to find, in a sample of 38 children age 4 through 12, only one child, a 10-year-old, who exhibited an adult pattern of judgments about material things. Sixty percent of the 4-year-olds and 25% of the 6-year-olds showed no evidence of having even a preliminary concept of matter or "stuff" that encompassed animals, liquids and powders, as well as inanimate objects (Carey 1991, 279). Review of other research indicates that young children also lack an equivalent of the adult concept of mind. Very young children, even younger than 3 years of age, may begin to learn concepts such as "knowing," "pretending," "thinking," "remembering," and "dreaming," which bear relationships to concepts in adult conceptual systems and which they use to communicate with adults and other children (Bretherton and Beeghly 1982; Johnson 1982; Shatz, Wellman, and Silber 1983). When young children use the word "mind," however, research indicates that they mean something very different than what adults mean.

Johnson and Wellman asked children, first graders to ninth graders, questions about the brain and the mind and what you need them for or can do with them (1982). Because young children are less familiar with the term "mind" than the term "brain," the investigators decided "to ensure relative familiarity with the term 'mind'" by not questioning children younger than first graders in this study (ibid., 226). Even so, the first graders made no distinction between the functions of the brain and the mind. Ninth graders, in contrast, made significant distinctions, particularly with respect to the role of the brain but not the mind in breathing, sneezing, and other actions which adults may characterize as involuntary and in seeing, hearing, and other perceptual acts. When asked "whether the brain and, separately, the mind could be seen or touched if one's head was opened up" (ibid., 226), none of the first graders answered both that the brain could be seen and touched but that the mind could not. Almost all the ninth graders gave this adult response. And when first graders were asked "if you didn't have a mind, could you have a brain?" and "if you didn't have a brain, could you have a mind?," most responded affirmatively to both questions. None of the ninth graders responded that way.

The responses of the first graders do not reflect an adult-like concept of mind or suggest that still younger children have anything approaching "a fundamental understanding of mental phenomena" as such. The response of one 5-year-old in Broughton's study seems to better represent the situation of young children in this regard (1978). Broughton asked children of various ages, as well as young adults, a series of questions from a semi-structured questionnaire, to determine "how thinking about knower and known, self and reality, develops," probing for clarifications and the grounds of the subjects' judgments (ibid., 78). After guessing, in response to a question about the mind, that "the mind is your head, isn't it?," the 5-year-old said, "I don't know what minds are" (ibid., 82).

Because young children may know about thinking but not minds, the question whether they distinguish between mental phenomena and physical objects is ambiguous and can be interpreted at least two ways. First, do young children distinguish in some ways between ideas and actual referents--for example, between thoughts and bicycles? Second, do they specifically identify thoughts as mental phenomena and bicycles as physical objects and distinguish between them in those terms? Piaget correctly gave a negative answer to the second question; Estes, Wellman, and Woolley correctly gave a positive answer to the first. In other words, Estes, Wellman, and Woolley established that young children are able to make many valid distinctions between existents which adults regard as mental and others which adults regard as physical, but not that young children understand the distinction between mental phenomena and physical objects.

The practice of using adult concepts such as "physical," "mental," "subjective," and "experience" in unqualified fashion to describe the understanding of young children, who do not yet possess equivalents of those adult concepts, threatens to undermine research findings. Describing children's concepts and beliefs requires close comparisons of conceptual systems and careful identification of adult concepts which children do not yet possess, to avoid their unwarranted importation. As Carey cautioned, "one cannot simply state the child's beliefs in terms of adult concepts" (1991, 288). Children who have not yet attained a given concept may conceptualize its referents some other way. Only by refraining from characterizing children's conceptual systems in terms of advanced adult concepts might one discover clues as to the actual structures of those systems.

Inadequately distinguishing adult from child knowledge has led to claims that the young child is an ontological dualist who shares "with adults the Cartesian view of human talk and action" and who recognizes that persons are "things which think" (Olson, Astington, and Harris 1988, 1, 11). The suggestion that young children can appreciate the meaning of the expression "a thing which thinks" does disservice to Descartes, by giving his words unintended literal meaning. Young children can conceptually identify different modes of thinking, given salient instances involving simple situations, but have much to learn about relationships among thoughts and about persistent cognitive and evaluative features identified by the adult concept of mind. Flavell, Green, and Flavell recently found, for instance, that many 6- and 7-year-olds do not attribute thoughts or ideas, or any brain activity, to persons who are awake but sitting quietly, waiting, and that most preschoolers are almost certainly not "aware of the continuous, nonstop nature of mental activity" (1993, 396). They have not drawn the "dualist" distinction which Descartes--whatever his metaphysics and methodology--drew between all external cognitive objects ("all things") and "a thing which thinks, that is to say a mind or a soul" (Method 4; Meditations 2, 4; emphasis added).

Lacking the concept of mind, young children come to organize thinking, knowing, remembering, and similar actions as things you do with your brain. The task of conceptualizing brains or other internal organs, such as hearts, while more complex than the task of conceptualizing readily tangible and visible body parts, such as feet or eyes, is far simpler cognitively than the task of conceptualizing minds. The tendency to associate certain actions with the brain is evident among 4-year-olds, according to another study by Johnson and Wellman (1982), and firmly established by the school years. Kindergartners tended to believe that the brain was needed mostly for actions that required thinking or knowing--for instance, they included reading because, as they explained, "you need to think to read" (ibid., 225). They included only certain feelings which were directly related to thinking, such as feeling sure or curious, tending to exclude other feelings (e.g., sad, scared), as well as other specific actions that the investigators classified as perceptions (e.g., see, hear), simple motor actions (e.g., talk, walk), and involuntary actions (e.g., cough, sneeze).

Older primary school children did tend to regard additional actions as needing a brain, but their underlying view of the brain's function as thinking was remarkably resilient. They frequently judged that you needed a brain to talk and walk, for reasons similar to those which kindergartners gave for including reading. You cannot talk without a brain because "you wouldn't know what to say," and you need a brain to walk because "it helps you know where your feet are going" (ibid., 225, 227). Some children did include seeing with the actions needing a brain--because they recognized that "you have to think about what you're seeing" (ibid., 225). Most continued to regard the brain as unnecessary for perceptions and involuntary actions. Even those who received formal training regarding the role of the brain in these actions, as part of the normal fifth grade school curriculum, did not alter their restricted view of the brain's functions.

There are plausible explanations for the tendency of preschool and primary school children to exclude perceptions, involuntary actions, and many emotions from the category of things requiring a brain. For one, their direct experience does not support the notion of brain involvement. Actions such as thinking, guessing, and pretending, which researchers may classify as intentional, "appear to be caused by the self," as Johnson has noted, but perceptions and emotional experiences "by contrast typically appear as caused by the world" (1988, 51). Pillow has noted that perceptual experience "feels like direct contact with the environment rather than a constructed representation."

In contrast, volitional, effortful activities generally provide cues to their occurrence that persist in memory traces and can be used to determine the origin of a memory.... The availability of such information suggests that knowledge of intentionality and mental effort should be gained early.

"Deliberate, effortful activities," he summarized, "seem more likely to leave cues to their occurrence than do more automatic processes" (1988, 21-22). Philosopher Ayn Rand noted that the process of integrating sensations into percepts is automatic and nonvolitional and that an emotion is "an automatic response proceeding from an evaluation of an existent" (1990, 29, 32). Furthermore, children can and do observe that other body parts, such as eyes and ears, play a role in seeing and hearing (Flavell 1978, 51) and that one may feel many things, such as fright, with one's whole body. Children thus already understand a role of the body, or its parts, in actions other than those closely related to thinking.

Children may organize thinking, guessing, pretending, remembering, and feeling sure and curious, in contrast, by understanding these processes in terms of the brain. While younger primary school children may know relatively little about brains, having virtually no idea of neuroanatomy and physiology (Nagy 1953), how much they know about a group of existents is a different issue than whether or not they have conceptualized and can distinguish them from all others (Rand 1990, 237). Most school children appear to have some conception of the brain, preeminently mentioning it as a content of the head (Gellert 1962; Nagy 1953). That they rely on the concept of brain (or proximate tangible body part such as the head) to organize their understanding of the various modes of thinking is the surest indicator that they have not formed an equivalent of the adult concept of mind. The adult concept of mind identifies the relationships and unity of various modes of thinking as cognitive processes, experientially, not in terms of their dependence on the brain or other body part.

Children do experience what adults call mental processes, such as thinking, and even think about thinking--as something people "do with their brains." They must extend their knowledge and cognitive powers considerably further to form the adult concepts needed to think about thinking as a mental activity that people do with their minds.

II. A Questionable Supposition

Historically, one fact more than any other has lent credibility to the notion that persons form the concept of mind introspectively. Philosophers and scientists have noted that one's only direct experience of consciousness is of one's own consciousness, that one's knowledge of the minds of others is inferred, not direct. A. J. Ayer took, as a starting point, "the propositions that I can have direct knowledge of my own experiences and that I cannot have direct knowledge of anyone else's" (1964, 348). "I cannot observe another mind or its acts," noted H. H. Price (1970, 162). "Self does not experience the experience of other directly," noted R. D. Laing; rather, self's knowledge of other's experience "is based at any age of self or other entirely upon inference" (1969, 5-6). "An individual's consciousness, as such, is inaccessible to others," reiterated Rand; "it is only when mental processes reach some form of expression in action that they become perceivable (by inference)" (1971, 997). "Any private act is by its nature known by another only through the use of the self in imagining what one would feel, think, or experience in a similar situation," noted Lewis (1983, 169). As Damon and Hart emphasized, "one has access to the self in a manner impossible with any other person, no matter how intimate the relationship" (1988,176).

Adults typically recognize the private nature of thinking and feeling, and adolescents and younger children make related observations. A fourteen-year-old subject in Broughton's study commented: "I know what I feel about things. And I don't know someone else" (1978, 88). Even preschool children, who lack many of the concepts of older persons, know that a picture in your head cannot be seen by others.

The undisputed inferential nature of one's knowledge of others' thoughts and feelings may make it seem inescapable that each person learns to think in terms of minds through an inwardly directed cognitive process. Direct knowledge of one's own mind as such may seem to be the necessary foundation for inferences that other persons have minds. James asserted that, in "the introspective study of the adult consciousness, . . . the first and foremost concrete fact which every one will affirm to belong to his inner experience is the fact that consciousness of some sort goes on" (1984, 139-40). Estes, Wellman, and Woolley claimed that, in acquiring knowledge of mental entities, one apprehends them "as first-hand, subjective experiences" (1989, 58). According to Damon and Hart, the conception of one's I, or subjective self, demands "greater introspection and reflectiveness" than conceptions of other aspects of the self (1988, 128-29). Hoffman supposed that a child might come to develop a sense of "the other as having his own personal identity--his own life circumstances and inner states beyond the immediate situation," after coming to understand this about himself first.

It seems reasonable that at some point the child develops the cognitive capacity to integrate his own discrete inner experiences over time and to form a conception of himself as having different feelings and thoughts in different situations but being the same continuous person with his own past, present, and anticipated future.

After thus integrating his own inner experiences and forming a conception of himself, "he should soon be able to perceive" a similar "coherence and continuity" in others (Hoffman 1975, 612-13; emphasis added).

The list of figures in philosophy who have made similar suppositions is long. Descartes noticed, while searching for a true and certain first principle by his method of doubting everything that he could doubt, "that whilst I thus wished to think all things false, it was absolutely essential that the 'I' who thought this should be somewhat" (Method 4). Apparently, one can think about one's own mind even while not recognizing the existence of anything--or anyone--else. Locke accepted the Cartesian approach, holding that one has "an internal infallible perception" of one's own being as a "conscious thinking thing" (Essay 2.27.17; 4.9.3). Price maintained that one knows "from introspection" what acts of thinking and perceiving are and that one knows "what it is for such acts to be combined into the unity of a single mind." He used the word mind in "the ordinary literal sense," "the sense in which one applies the word to oneself" (1970, 162, 164). Rand affirmed that one's "being conscious" is the only fact of reality that one has to grasp to conceptualize one's self or mind and that grasping it enables one to infer "that other human beings also possess the ability to have mental entities" (1990, 145, 255). Apparently one can form the concept of mind in her view, even if, like Howard Roark in the beginning of her novel The Fountainhead, one had "never learned the process of thinking about other people" (1943, 21).

My major thesis, in contrast to these views, is that whatever the variability between persons or within any given individual's cognitive history, knowledge of one's own mind as such and knowledge of the minds of others as such emerge simultaneously. One commits the logical fallacy of composition if one supposes that, because one must conceptualize processes such as thinking, remembering, and imagining in some rudimentary introspective fashion, so one must conceptualize one's mind as a whole also introspectively. What is true of thinking, remembering, and imagining--that one can conceptualize them by reference to one's own experience--is not necessarily true of one's mind. In the remainder of this paper, I argue on epistemological grounds that, indeed, one cannot form the concept of mind by reference only to one's own experience. I also review further scientific research and outline the cognitive requirements of forming this concept.

III. A Capacity to Recognize

The idea that one can directly conceptualize one's own mind neglects fundamental and frequently emphasized aspects of conceptual cognition. Theories of concepts, or universals, attempt to account for the relationship between a "set of things" and the "same name" by which we call them (Plato, Republic 596) and presuppose that concepts bear relationships to multiple tokens or instances. Concepts, noted Rand, "represent classifications of observed existents according to their relationships to other observed existents" (1990, 47). Price noted that it is repetition in the world--resemblances between different things--that makes conceptual cognition possible. He described two essential manifestations of having a concept: being able to recognize concept instances, when and if one encounters them, and being able to think of those instances even later, in their absence (1962, 35-36, 276-77).

The nature of conceptual cognition precludes conceptualizing one's mind by simple inward observation. Hume's putative effort to "catch" himself by such observation reveals a distinctly nonconceptual stance.

For my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe any thing but the perception. (Treatise 1.4.6)

Any attempt to catch oneself as subject of cognition or to conceptually identify one's mind, by thinking within a restricted context that excludes one's knowledge of others, involves a failure of perspective, comparable to trying to conceive of forests while constricting one's perception and thought to individual trees. While considerable scientific research has focused on children's developing awareness of "mental" processes, the common supposition that persons can directly conceive of minds and recognize their own mental processes as mental has led to scientific neglect of the development of the actual concept of mind. No one can form the concept of mind, or learn to think of mental processes as mental, by focusing inwardly on one mind without considering its relationship to other similar existents, its similarity to other minds.

Many philosophers, including many of those cited earlier, have not only supposed the possibility of direct conceptualization of one's own mind or consciousness as such, but have made this supposition without recognizing its apparent inconsistency with their own theories of concepts. Descartes held, for instance, that "universals arise solely from the fact that we avail ourselves of one and the same idea in order to think of all individual things which have a certain similitude" (Principles 59). If universals arise solely from one's awareness of similitudes among things and one has only one mind, how can one arrive at the universal "mind" independently of one's knowledge of others? Locke held that making general ideas "is the workmanship of the understanding" that sorts many things according to "the similitude it observes" amongst them, so that a general word signifies or represents "many particulars" indifferently (Essay 3.3.11-13). How can one arrive at the general idea of self or consciousness through an internal perception, when one must observe the similarity of many particulars to arrive at a general idea? Any internal perception of one's own consciousness, "as far as that consciousness extends" (Essay 2.27.17), is singular--a "perception" of only one particular, not many. Price held that, in being aware of a universal, one is "aware of it as recurrent." He endorsed Locke's observation that abstract ideas "have their foundation in the similitude of things" (Price 1962, 61, 302; Essay 3.3.13). One can conceptualize acts of thinking and perceiving "from introspection," as similar acts recur innumerable times in direct experience, providing the requisite material to conceptualize them. But how can one know what minds are by applying the word 'mind' to oneself alone? One has only a single mind. One cannot grasp the similitude of minds or be aware of "mind" as recurrent introspectively.

The difficulty of maintaining that one can directly conceptualize one's mind is particularly clear given the framework of Rand's Objectivist epistemology (1990). Forming a concept of something requires an action of consciousness, a certain way of regarding the existent being conceptualized. One must regard it, according to Rand, as a unit--that is, "as a separate member of a group of two or more similar members" (ibid., 5-7). Obviously, one cannot regard one's mind as a unit by restricting one's range to internal data. Rand described similarity as "the relationship between two or more existents which possess the same characteristic(s), but in different measure or degree" (ibid., 13). She held that concept formation involves a measurement process which one performs at least implicitly and should often perform explicitly: one regards existents as units because, even though measurably different, perhaps in every measurable regard, all their measurements of a fundamental characteristic(s) fall within a specifiable range. The process of concept formation then entails observing that range, or distinguishing characteristic(s), while omitting from consideration the particular measurements of each existent within it. A concept is "a mental integration of two or more units possessing the same distinguishing characteristic(s), with their particular measurements omitted" (ibid., 13). If concept formation requires observing relationships between existents and integrating "two or more" in this fashion, how can one form the concept mind without learning the process of thinking about other people? Indeed, a concept subsumes not just two similar existents, but an indefinitely large number. Forming a concept, according to Rand, entails grasping that it applies to all entities of a particular kind--past, present, and future (ibid., 147). There are countless minds to be subsumed by the concept mind--and all but one of them lie outside the range of one's direct awareness.

The recent rediscovery, in some quarters, that context of knowledge is of significance, that an exclusive focus on the element of similarity is "insufficiently constraining" (Murphy and Medin 1985), does not obviate the need to attend to the crucial role of the element of similarity. As Rand emphasized, concept formation is a contextual process that involves first differentiating two or more existents from other existents.

Concepts are not and cannot be formed in a vacuum; they are formed in a context; the process of conceptualization consists of observing the differences and similarities of the existents within the field of one's awareness (and of organizing them into concepts accordingly). (Rand 1990, 42)

Similarly, H. W. B. Joseph described the standard elements of differentia and wider genus as terms in which one defines a concept (1961, 86). Only within a given context of knowledge can one determine which characteristic(s) among those shared by a group of existents is distinguishing, but the element of similarity remains "crucially involved in the formation of every concept" (Rand 1990, 13).

Although Rand did not notice the contradiction between her theory of concept formation and her view that one can conceptualize one's own mind directly, she addressed in a workshop discussion a very similar issue with respect to the notion of God.

God isn't even supposed to be a concept: he is sui generis, so that nothing relevant to man or the rest of nature is supposed, by the proponents of that viewpoint, to apply to God. A concept has to involve two or more similar concretes, and there is nothing like God. He is supposed to be unique. Therefore, by their own terms of setting up the problem, they have taken God out of the conceptual realm. And quite properly, because he is out of reality. (ibid., 148)

Minds are in reality--as attributes of certain living organisms. Those who suppose, as Rand herself did, that one can conceptualize one's mind introspectively, by grasping directly one's "being conscious," improperly take the mind out of the conceptual realm. They imply that one need consider nothing relevant to other persons or other conscious entities, that one can form the concept by treating oneself initially as sui generis, which is untrue. The concept of mind, no less than any other concept, must involve "two or more similar concretes." It is only because our minds are similar, and one is not altogether unique, that we can grasp those similarities and conceptualize our minds.

Rand included the concepts consciousness and self in a small set of axiomatic concepts which identifies the base of knowledge (ibid., 55-57, 252). To form other axiomatic concepts, one must mentally integrate two or more units and grasp an element of similarity--in the case of the axiomatic concept existence, for instance, the fact that the existents exist (ibid., 59). The concept existence subsumes all existents, an indefinite number. Rand's claim that one can somehow form another axiomatic concept, the concept self, directly, introspectively, that is, without integrating even two concretes, fundamentally contradicts her theory of concepts. She did not identify this apparent contradiction nor offer an explanation.

Each person instantiates or exemplifies the concept of mind only once. This concept "reflects understanding of an integrated mental existence--that it is the same mind being used in different ways, encompassing different cognitive processes and states" (Johnson and Wellman 1982, 222). To form this concept, it is not just certain processes and states that one must conceptualize, but their overall "coherence and continuity." One must bring one's consciousness, as one unit, into conceptual terms--which means that one must grasp the relationship, the element of similarity, between one's own mind and the minds of others. No manner of cognition directed inward provides one with adequate material to do this. One cannot find the perspective needed to form the concept mind through direct introspective awareness. Because one has experience of only one's own mind, one must conceptualize it by mentally integrating directly and indirectly available material, which makes the formation of this concept particularly challenging.

Some might deny this complexity by claiming that, in addition to proper names which identify particular entities, "singleton" concepts are possible. D. M. Armstrong has claimed that certain universals may be "only instantiated once"--in other words, that "a thing may be of a type without anything to resemble" (1989, 49, 121-22; see also Flavell 1970, 984; Strawson 1959, 99). Such an objection, in this context, would need to be addressed in detail only on the proverbial desert island, because theorists agree that having a concept entails being able to recognize appropriate existents when and if one encounters them. As Peter Strawson explained, if one ascribes predicates of a certain class to one individual, one should "be prepared, or ready, on appropriate occasions, to ascribe them to other individuals." He recognized that

it is a necessary condition of one's ascribing states of consciousness, experiences, to oneself, in the way one does, that one should also ascribe them, or be prepared to ascribe them, to others who are not oneself.

This means "that the ascribing phrases are used in just the same sense when the subject is another as when the subject is oneself" and that "one should have a conception of what those appropriate occasions for ascribing them would be" (Strawson 1959, 99). As Price noted, "to have a concept is at least to be able to recognize instances when and if they are observed" (1962, 35-36). Every human being is, of course, afforded abundant appropriate occasions for ascribing minds to others, for recognizing that subjects other than oneself exist, since we all function from birth within social networks, encountering people who have minds. A person who does not explicitly recognize that others have minds has not formed the concept of mind.

Strawson's reasoning does not establish that young children do indeed ascribe "states of consciousness" or "experiences" to themselves. Research has established that they conceptualize actions such as seeing, thinking, pretending, and remembering. They may recognize instances of remembering "in the presence" of those instances, when they remember something or when they understand that someone else does, and "in their absence"--for instance, when they later recall such instances of remembering. Research does not support claims, however, that young children ascribe "states of consciousness" or "experiences" to themselves or to others. Young children conceptualize actions which are, in adult terms, actions of consciousness, and adults with mature conceptual systems have classified concepts of these actions as concepts of consciousness or of mental action, but there is a difference between conceptualizing an action which adults know to be mental and identifying the action as mental. Young children do the former without the latter. Despite frequent claims that young children have theories of mind and are little Cartesians, they have not formed the adult concepts of mind or consciousness which would enable them to recognize actions as mental actions or actions of consciousness.

An essential aspect of the formation of the adult concept of mind is the complex cognitive integration of self and others which enables one to recognize instances of minds "in their presence," as in one's ever present direct experience of one's own mind or in one's inferences about others' direct experience of their minds. The concept mind also enables one to think about other people's minds "in their absence," when they are away. The application of the concept of mind to others is no mere afterthought, no more so than the application of the concept to oneself.

In the final section, I bring together these epistemological considerations and scientific research findings (including those reviewed earlier) to place the formation of the concept of mind in developmental perspective.

IV. The Attitude of Reciprocity

The key to understanding how a person actually brings his or her mind into explicit conceptual terms is grasping that, on this level of abstraction, self-consciousness and consciousness of others emerge simultaneously. This is not to suggest that one's knowledge of oneself and one's knowledge of others are identical. Self-knowledge and knowledge of others obviously have different cognitive objects. My claim is rather that a person identifies the facts that he or she has a mind and that others have minds as an integrated cognitive process, the ultimate culmination of a long conceptual development.

Children begin this developmental process by conceptualizing not mental processes or minds, but themselves and other people as "objective selves" which exist in the world (Johnson 1988, 57). Carey found that young children "have mapped the words 'person' and 'people'" onto a concept with the same extension as the adult's (1985, 183). Although people in non-Western cultures may experience their existence differently in some ways than people in Western cultures, the concepts of person and self appear to be fundamental across all cultures, with all adults distinguishing "between actions of the self as opposed to those of another" (LeVine and White 1986, 38). As Rand pointed out, "there are no attributes without entities, there are no actions without entities" (1990, 264). A child must initially bring into conceptual terms entities which act; only then can he or she conceptualize the actions of those entities, to study them separately.

Most children conceptualize eyes, mouths, and ears, correctly labeling these parts, before two years of age (Bretherton, McNew, and Beeghly-Smith 1981). Young children learn that one sees with one's eyes, tastes with one's mouth, and hears with one's ears. The dependence of concepts such as seeing and tasting upon knowledge of acting entities is graphically evident in the learning of sign language, where hearing-impaired children may grasp and convey these concepts by reference to their bodies and the actions involved. The symbol in Signed English for seeing, for instance, is two fingers moving outward from one's eyes. Young children not only form concepts that subsume their own and others' actions of seeing and hearing, they also conceptualize actions of wanting, knowing, remembering, thinking, pretending, dreaming, and so on. Analyses of data collected by a variety of techniques has demonstrated that children begin to develop such concepts during their second and third years. By the age of 4, they have begun to establish the pattern that you walk and run with your feet, see with your eyes, hear with your ears--and think with your brain. In a young child's view, you need your brain for thinking and related actions such as knowing, guessing, remembering, and feeling sure or curious--a list that continues to grow during the primary school years.

Just as the world offers the child two or more units, the requisite recurrence, to form concepts such as people, eyes, ears, and nose, so direct experience provides him or her with the requisite recurrence to form concepts such as seeing and hearing, wanting, feeling curious, and pretending, thinking, remembering, and dreaming. Adults with a far greater level of knowledge may guide children in this learning process (Dunn, Brown, and Beardsall 1991). Children's interactions with parents, and with siblings and other children, especially in play or in conflict situations (Howe 1991), may supply important motivation to conceptualize these actions, as well as additional opportunities for learning and assimilating others within this knowledge domain. These influences do not alter the fact that any given child has direct access to sufficient material to form these concepts.

The situation is very different with respect to the mind itself. While most adults recognize that thinking, remembering, and imagining are mental processes, the young child is far from attaining that level of knowledge. He or she does experience a mind--awakening each morning to the same environment, to memory, to the automatization of previously formed concepts, to the use of newly acquired cognitive skills, and to a growing range of interest in the environment and knowledge of particulars. Consciousness does not start afresh each day, tabula rasa, as though knowledge and skills learned in preceding days and years carried no current significance. While the child experiences "the unity of a single mind," it is precisely that unity which leaves him or her unable to bring it directly into conceptual terms. Conceptual cognition is a recognitive capacity. Only by grasping the similarity between two or more existents can one bring any one of them into conceptual terms.

The task of conceptualizing minds presents difficulties not presented by the task of conceptualizing body parts, such as brains. A child can see and touch both self and other persons and may learn about brains during the school years. He or she can place and depict anyone's brain with equal ease or difficulty. In contrast, a child cannot experience any other person's mind at all, ever. Indeed, he or she eventually must identify both the continuity and distinctness of each person's experience in order to form the concept of mind.

As a child acquires knowledge of actions such as seeing and hearing, and of things "you can do with your brain," such as thinking, he or she incorporates others within this domain. Because the child is not imputing minds or mental processes as such, he or she can easily recognize that others see, hear, want things, think, pretend, remember, and so on. The child has substantial evidence of such actions and actively ascertains specifics, within this limited context. Hoffman, for instance, described the behavior of one young child.

Marcy, aged twenty months, was in the playroom of her home and wanted a toy that her sister was playing with. She asked for it but her sister refused vehemently. Marcy paused for a moment, as if reflecting on what to do, and then ran straight to her sister's favorite rocking horse--which her sister never allowed anyone to touch--climbed on it and began yelling "Nice horsey! Nice horsey!" keeping her eye on her sister all the time. Her sister put down the toy and came running angrily, whereupon Marcy immediately climbed down, ran directly to the toy, and grabbed it. (1981, 71-72)

A child of this age may be capable not only of such strategic behavior, but on the threshold of explicitly conceptualizing her own and others' wants (Bretherton, McNew, and Beeghly-Smith 1981). Claiming that she imputes the mental state of wanting, however, is quite imprecise; she imputes wanting. To claim that she imputes mental states is to confuse our own adult knowledge with her more limited knowledge. As Johnson concluded, "it is, perhaps, young children's ignorance of minds" that allows them so readily to imagine "different people in different roles and contexts, reading off the implications for behavior" (1988, 58).

A child's knowledge of others is tied intimately, on this lower cognitive level, to his or her self-knowledge. A first grader, for instance, can grasp what it means for her older brother to have a nightmare and can discuss his nightmare with him--by relating it directly to her own nightmares (and any others about which she may already know). Having formed the concept nightmare and applying it to herself and others, she also likely uses it to refer to "nonpresent states" (Bretherton and Beeghly 1982, 906). Thus, she not only may recognize an instance of a dream when she awakens from one, or when her brother awakens and reports one, but may also remember and think about such instances even hours later "in their absence." Her method of directly relating particular dreams of other persons to her own dreams, and similarly with other actions, is effective in bringing those actions of others into her cognitive range and provides an indispensable foundation for her future development.

An enormous expansion in the breadth and precision of her knowledge of others, and herself as well, gradually occurs as she forms a concept which subsumes, as separate units, all of each person's thoughts, dreams, memories, feelings, and so on. To explicitly form the concept of mind, she must develop the insight that "my thought belongs with my other thoughts" and "with none besides" (James 1984, 140-41), that all of her thoughts, by virtue of their relationships as thoughts, "cohere mutually"--and similarly that all of each other person's thoughts also "cohere mutually."

Researchers are developing a wealth of information about children's developing knowledge of what others see, want, know, think, dream, remember, and so on. Young children learn that whether or not persons see something at all depends on variables such as whether their eyes are open and which way they are facing. Later, they also recognize that another person standing in a different place sees the same object differently (Flavell 1978). In standard false-belief experiments, 3-year-old children typically fail to understand that another person is likely to form a false belief if not privy to vital information which the child is given (Perner, Leekam, and Wimmer 1987). Indeed, 3-year-olds typically can describe neither another's false belief, even when given strong and redundant cues (Moses and Flavell 1990), nor their own past false beliefs, even moments after they discover that they are false and change them (Gopnik and Astington 1988). In contrast, 5-year-olds can describe another's false beliefs, correctly predicting another's actions in false-belief experiments, and can describe their own past false beliefs. Taylor was surprised to discover that many 4-year-old children who saw a complete line drawing assumed that an observer could identify the depicted object after seeing only a small, nondescript part of the drawing, and sometimes even only a tiny edge of the piece of paper with no marks on it. In contrast, it is obvious to 8-year-old children "that no one could ever identify an object on the basis of so little information" (Taylor 1988, 711).

During the early school years, children begin to apply previously formed concepts recursively, to describe "different persons' concern about each other's mental states" (Perner 1988, 271). For example, a student seeing a classmate, John, kick Mary under the table might conclude that John knows that Mary does not know that the teacher is coming (ibid., 272).

Barenboim found that, as children mature, they tend decreasingly to describe persons in behavioral terms, tending rather to use psychological constructs, including personality characteristics and enduring psychological dispositions during middle childhood and psychological comparisons during adolescence, so that "by late adolescence the relatively heavy use of behavioral comparisons 'sticks out like a sore thumb'" (1981, 139). Bernstein found that adolescents become increasingly aware that they themselves and others have personal systems of values and beliefs which govern action (1980, 240-41). Although further research is needed, it is already clear that children are constantly learning how to think about other people.

Insofar as children develop an appreciation of what other people cannot--and actually do--see, want, think, believe, remember, and so on, as evidenced in their maturing verbal descriptions and ability to predict others' behavior, they may be said to have the adult concept of mind implicitly--if that means that they are gathering the material, in their direct knowledge of themselves combined with their knowledge about others, which will later "be integrated by that concept" (Rand 1990, 6). On this level, recognition of minds remains dependent upon interaction with others and below the level of enduring explicit formulation.

To take the next step of reaching the concept of mind explicitly, a person must learn to regard himself or herself, the full extent of his or her thinking, remembering, imagining, dreaming, and similar actions, in abstraction from his or her brain, as a unit--that is, as "a separate member of a group of two or more similar members," only one of many such units. This attitude of regarding oneself as a unit is an essential aspect of psychological maturity and constitutes a radical departure from the earlier childhood method wherein one made the actions of others knowable by establishing only their similarity to actions which one can conceptualize introspectively. No such introspective primacy applies with respect to the specific higher-order task of conceptualizing minds: without mentally integrating one's own and other minds, grasping the similarity between them, one cannot bring one's own mind into conceptual terms. One cannot form the concept of mind or "catch" one's subjective self without learning to think about others.

Thus, an essential aspect of the process of forming the adult concept of mind is understanding the relationships among another person's thoughts, memories, dreams, and so on. One must learn to place all such actions of another person together, exclusively within that person's own context. One may then grasp the crucial element of similarity between the other person and oneself. Forming the concept mind involves grasping not just that another person has an isolated dream or memory similar to one's own or that the person sees or thinks something much as one has oneself, but that every such action of the other person fits within that person's unique, individual context, which informs it and gives it significance. Once one makes inferences about the relationships among the various thoughts of another person and one grasps the element of similarity between oneself and others with respect to each person having his or her own context, one has the two or more units required to form the concept mind and can cognitively integrate them, bringing one's own and other minds into conceptual awareness simultaneously, in one cognitive action.

The dual necessity of grasping the relationships among actions which one infers in another person and of incorporating, without reservation, the total of one's own inner experiences as one unit--the only direct experience of a mind one has, but inadequate material in itself--is what puts the adult concept mind well beyond the reach of young children.

The concept mind represents an enormous condensation of knowledge, enabling one to frame all that one knows about one's own or any other person's experiences. In order for this awareness to move beyond "the first faint beginnings of an abstract idea" (Price 1962, 73), one must identify one's observations in some "concrete, specific, sensory form" (Rand 1990, 165), wrapping it up "in one short sound" (Locke, Essay 2.22.7). The ability to think in abstraction about other minds and one's own requires that one learn a word, such as mind or self, that stands for all those existents that one is trying to integrate, an indefinitely large number--the mind of each and every person. When one accomplishes this, one can think specifically about one's own mind and about the mind of anyone else whom one knows, whether that person is present or absent, as well as the mind of anyone else with whom one comes into contact.

With this cognitive development, the notion of self may take on new meaning. Children's broadly based self-understanding develops in a variety of ways, but "the I more than any other aspect of the person requires a special self notion to express" (Damon and Hart 1988, 6). A tendency emerges, with approaching adulthood, to construe the core aspect of the self as the mind. A 14-year-old in Broughton's study said: "Yourself is more your mind . . . , the way your thoughts go," and another, when asked about the self, said it is "the inside of the person. . . , the way their mind works" (1978, 87-88). These youngsters begin to echo the sentiments of philosophers such as Descartes who regarded his I as his mind or soul, Locke who held that one's consciousness is "that alone which makes what we call self" (Essay 2.27.21), and Rand who similarly held that "your self is your mind" (1957, 1030).

By conceptualizing minds, one becomes able to think systematically about how each person's experiences, context of knowledge, value judgments, attitudes, methods of mental functioning, and other mental characteristics influence his or her current experience and also how these characteristics differ from one person to another, greatly increasing the range and precision of one's subsequent inferences about others' mental processes. The ability to think about any person's inner world in total, encompassing everything one knows about the experiences of that person, constitutes an advanced method of understanding self and others, which young children do not have explicitly available to them and which underlies the entire realm of psychological thought.

Although research is sparse regarding typical milestones of the development of the explicit concept of mind, Bernstein found that major transformations in adolescents' self-perception occur after age 15 (1980, 243-44). Johnson found that college juniors have a "pervasive understanding of the brain as distinctly an organ with nerves, and the mind as integrally related to the soul and subjective self" (1982, 470). A review of Broughton's research suggests, however, that not all young persons complete the task of conceptualizing minds with equal ease. Even some college students in their twenties appear to lack a coherent concept of mind, failing to recognize the distinction between mind and brain. "The mind is the brain, the actual physical brain," said one 22-year-old. "You are what you see, what the body can do," and "I think it is wrong to say you have a self" (1978, 94).

The theory presented in this article regarding the formation of the concept of mind has broad implications in ethics, education, mental health, and other fields pertaining to human development. The scope of these implications may be gauged by briefly reviewing one of Rand's theories and one of Piaget's. Rand emphasized that thinking is a volitional process. She held that, "in any hour and issue of your life," you face a choice "to think or not to think" (1957, 1012). Research has demonstrated that even young children do know about thinking. They know it helps to know what you are doing--for instance, "where your feet are going"--and to think about what you say and see, and to "use your brain" other ways. Because making choices presupposes some awareness of alternatives, these findings support Rand's theory of volition. She assumed, however, that one can conceptualize one's mind directly. Branden, in his elaboration of Rand's theory, maintained that one cannot escape the implicit knowledge that the function of one's mind is volitional, that such knowledge is implicit in anyone's consciousness, even a child's, "by direct introspective awareness" (1969, 41). This theory needs to be revised to take into account both the complexity of the formation of the concept of mind and its significance. An adolescent who acquires explicit knowledge of minds, for instance, will consequently uncover many possibilities of mental action which were previously hidden and inaccessible. Those actions, when actually taken, are thus not simply the result of volitional choice. If they are not taken, this may be due to their remaining hidden and inaccessible, not simply to culpable evasion or a choice not to think. Only after explicitly forming the concept of mind could one "know what one's mind is doing" or understand the choice to think or not as the choice "to focus one's mind or not" (Branden 1969, 40-43).

Inhelder and Piaget postulated a relationship between the growth of formal thought and "the fundamental problem of adolescence." It is not puberty or "physiological growth alone" which they considered crucial, but a fundamental social transition--"the fact that the individual begins to take up adult roles" (1958, 335-36).

As opposed to the child who feels inferior and subordinate to the adult, the adolescent is an individual who begins to consider himself as the equal of adults and to judge them, with complete reciprocity, on the same plane as himself. (Ibid., 338-39)

Inhelder and Piaget apparently sensed that an important relationship exists between adult thinking and adult roles, but their account of the relationship is incomplete. Bruner took note of their suggestion that, "as adult roles must be filled, the young human is forced to cope with futurity and possibility and that the apparatus of thought responds to these pressures" (Bruner 1959, 370). He added that "we need a more elaborate account of how this comes about."

Intellectual growth at this point depends upon the conceptualization of minds, which does not occur automatically in the maturing organism. Conceptualization requires that one take the specific attitude of reciprocity which Inhelder and Piaget mention, regarding oneself "as the equal of adults" and judging them "on the same plane" as oneself. This attitude is none other than the attitude I have been describing, of regarding oneself as a unit--one of a group of two or more similar existents, all human beings. The adult stance, which social institutions can facilitate or thwart, but the individual must adopt, is one of reciprocity. It is only by taking an attitude of reciprocity that the adolescent can conceptualize his or her own mind and learn to identify thinking, remembering, dreaming, and so on as mental processes. With new concepts, a developing explicit awareness of mind and reality, he or she may henceforth acquire a significant ability to introspect and learn to monitor and direct his or her own overall cognitive and emotional development.

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