The Development of Theory of Mind in Early Childhood

1Institute of Child Study, University of Toronto, Canada
2School District 10, New Brunswick Education, Canada

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The most important development in early childhood social cognition is the development of theory of mind.1,2 Its development during the first five years of life is described in this article, as well as factors that influence its development, and the consequences of its development for children’s lives at home and school.


Social cognition is at the heart of children’s ability to get along with other people and to see things from their point of view. The basis of this crucial ability lies in the development of theory of mind.3,4 “Theory of mind” refers to our understanding of people as mental beings, each with his or her own mental states – such as thoughts, wants, motives and feelings. We use theory of mind to explain our own behaviour to others, by telling them what we think and want, and we interpret other people’s talk and behaviour by considering their thoughts and wants.


The development of theory of mind from birth to 5 years of age is now well described in the research literature4,5 – or at least, we can describe how infants and children behave in experimental situations as well as in natural settings. There are problems, however, in interpretation of the findings. Some researchers claim that even babies are aware of other people’s thoughts and wants while others think that this understanding does not develop until the toddler or preschool years. This contradiction can be resolved by taking a developmental view of theory of mind – that is, early-developing intuitive awareness later becomes more reflective and explicit.5 Moreover, children’s developing language abilities play an important role in this transition.6

Research Context

Children’s awareness of thoughts, wants and feelings is inferred from what they say and do in naturalistic and experimental situations. Natural settings show the child’s abilities to interact with others in the real world.7 Experimental settings, where children are questioned individually about hypothetical scenarios, reveal the precise level of a child’s independent understanding.8 

Key Research Questions

  1. What are the typical developments in theory of mind from infancy to age 5?
  2. What factors, both those in the social environment and those internal to the child, influence the rate of development?
  3. What are the consequences of theory-of-mind development for children’s social competence and for their success in school?

Recent Research Results

Research shows that infants display behaviours that are important beginnings for theory-of-mind development (see details in Moore’s and Sommerville’s papers in the chapter on social cognition9,10).
By age 2, children clearly show awareness of the difference between thoughts in the mind and things in the world. In pretend play (e.g., pretending a block is a car), toddlers show that they can distinguish between an object – the block – and thoughts about the object – the block as a car.11 They also understand that people will feel happy if they get what they want and will feel sad if they do not.12 And at this age children see that there may be a difference between what they want and what another person wants.13 This developing awareness is seen in children’s language too: 2-year-olds talk about what they and others want and like and feel; when they are 3, they also talk about what people think and know.14

A crucial development occurs around 4 years of age when children realize that thoughts in the mind may not be true. For example, children are allowed to discover that a familiar candy box actually contains pencils, and then are asked what their friend will think is in the box, before looking inside it.15 Three-year-olds assume that the friend will know it has pencils inside, just as they now do, but 4-year-olds recognize that the friend will be tricked, just as they were. Three-year-olds also do not remember that their own belief has changed.16 If the pencils are put back in the box and they are asked what they thought was inside before opening it, they’ll say “pencils” not “candy” but 4-year-olds remember they thought it was candy. That is, 3-year-olds are not simply egocentric, i.e., thinking everyone knows what they know, rather, they come to understand their own minds and those of other people at the same time. By the age of 4 or 5 years, children realize that people talk and act on the basis of the way they think the world is, even when their thoughts do not reflect the real situation, and so they will not be surprised if their uninformed friend looks for candy in the box they know has pencils inside.

Some factors in the social environment influence the rate of typical development of theory of mind: for example, children show earlier awareness of mental states if their mothers talk about thoughts, wants and feelings,17 and provide reasons when correcting misbehaviour.18 Children with brothers and/or sisters are aware of mental states sooner than only children.19 The rate of development is also influenced by children’s participation in pretend play,20 their experiences of story-book reading21 and of talking with others about past experiences.22 Factors internal to the child that influence the rate of development include language abilities,23 and cognitive abilities that control and regulate behaviour (known as executive functions).24

Research shows that theory-of-mind development has consequences for children’s social functioning and school success. Children with more developed theory of mind are better communicators and can resolve conflicts with their friends;25 their pretend play is more complex;26 their teachers rate them as more socially competent;27 they are happier in school and more popular with peers;27 and their school work is more advanced in some ways.28 However, a well-developed theory of mind can also be used in antisocial ways, such as in teasing, bullying and lying.29

Research Gaps

We need to know more about how and why different environmental-social and child-cognitive factors affect the rate of theory-of-mind development, particularly regarding effective interventions for children whose theory of mind is less well-developed.

To date, the majority of studies involve middle-class, Western children. More research is needed with children from different backgrounds and cultures to investigate similarities and differences in theory-of-mind development.

How people act is governed not just by their thoughts and wants, but also by moral and social rules. Research is needed into how rule-based reasoning and theory of mind operate together in social cognition.

More research is also needed into the brain processes underlying theory of mind.


Theory of mind develops gradually, with intuitive social skills appearing in infancy and then reflective social cognition developing during the toddler and preschool years.

Three-year-olds know that different people may want, like and feel different things. By age 4 or 5, children know that people may think different things. They understand that sometimes a person may believe something that is not true but, in that case, what the person does or says is based on the false belief.

There are differences in the rate of typical development that partly depend on factors in the environment, such as family talk and disciplinary strategies, interaction with siblings, story books and pretend play, as well as factors in the child, such as language and cognitive control abilities.

There are consequences to theory-of-mind development that are seen in children’s social competence and success in school.

Implications for Parents, Services and Policy

Theory of mind is at the base of children’s social understanding. The implicit theory of mind seen in infants becomes more explicit during the preschool years and provides an important foundation for school entry.

Theory of mind is more like language than literacy, in so far as it is a system with biological roots that develops without specific teaching.

Nonetheless, environmental factors do influence its development. It can be enhanced by opportunities:

  • to engage in rich pretend play;
  • to talk about people’s thoughts, wants, and feelings, and the reasons why they act the way they do;
  • to hear and talk about stories, especially those involving surprises, secrets, tricks, and mistakes, that invite children to see things from different points of view (for example, Red Riding Hood doesn’t know that the wolf is dressed up as grandma).

Parents and caregivers can be made aware of signs, such as lack of pretend play or lack of shared attention and interest, that might indicate theory of mind is not developing in the typical way, which is the case with children at risk for autism, for example.30


  1. Flavell JH, Miller PH. Social cognition. In: Kuhn D, Siegler R, eds. Cognition, perception and language. 5th ed. New York, NY: Wiley, 1998; 851-898. Damon W, gen ed. Handbook of child psychology; vol. 2.
  2. Harris PL. Social cognition. In: Kuhn D, Siegler RS, eds. Cognition, perception, and language. 6th ed. Hoboken, NJ: Wiley; 2006: 811-858. Damon W, Lerner RM, gen eds. Handbook of child psychology; vol. 2.
  3. Astington JW. The child’s discovery of the mind. Cambridge, MA: Harvard University Press; 1993.
  4. Astington JW, Dack LA. Theory of mind. In: Haith MM, Benson JB, eds. Encyclopedia of infant and early childhood development. Vol 3. San Diego, CA: Academic Press; 2008: 343-356.
  5. Astington JW, Hughes C. Theory of mind: Self-reflection and social understanding. In: Zelazo PD, ed. Oxford Handbook of Developmental Psychology. New York, NY: Oxford University Press. In press.
  6. Astington JW, Baird JA. Why language matters for theory of mind. New York, NY: Oxford University Press; 2005.
  7. Dunn J. The beginnings of social understanding. Cambridge, MA: Harvard University Press; 1988.
  8. Perner J. Understanding the representational mind. Cambridge, MA: Bradford Books/MIT Press; 1991.
  9. Moore C. Social cognition in infancy. In: Tremblay RE, Barr RG, Peters RDeV, Boivin M, eds. Encyclopedia on Early Childhood Development [online]. Montreal, Quebec: Centre of Excellence for Early Childhood  Development; 2010:1-4. Available at: Accessed July 26, 2010.
  10. Sommerville JA. Infants’ social cognitive knowledge. In: Tremblay RE, Barr RG, Peters RDeV, Boivin M, eds. Encyclopedia on Early Childhood Development [online]. Montreal, Quebec: Centre of Excellence for Early Childhood Development; 2010:1-6. Available at: Accessed February 8, 2011.
  11. Kavanaugh RD. Pretend play and theory of mind. In: Balter L, Tamis-LeMonda CS, eds. Child psychology: A handbook of contemporary issues. 2nd ed. New York, NY: Psychology Press, 2006; 153-166.
  12. Wellman HM, Banerjee M. Mind and emotion: Children's understanding of the emotional consequences of beliefs and desires. British Journal of Developmental Psychology 1991;9(2):191-214.
  13. Meltzoff AN, Gopnik A, Repacholi BM. Toddlers' understanding of intentions, desires, and emotions: Explorations of the dark ages. In: Zelazo PD, Astington JW, Olson DR, eds. Developing theories of intention: Social understanding and self control. Mahwah, NJ: Erlbaum, 1999; 17-41.
  14. Bartsch K, Wellman HM. Children talk about the mind. New York, NY: Oxford University Press; 1995.
  15. Perner J, Leekam S, Wimmer H. Three-year-olds' difficulty with false belief: The case for a conceptual deficit. British Journal of Developmental Psychology 1987;5(2):125-137.
  16. Gopnik A, Astington JW. Children's understanding of representational change and its relation to the understanding of false belief and the appearance-reality distinction. Child Development 1988;59(1):26-37.
  17. Ruffman T, Slade L, Crowe E. The relation between children's and mothers' mental state language and theory-of-mind understanding. Child Development 2002;73(3):734-751.
  18. Ruffman T, Perner J, Parkin L. How parenting style affects false belief understanding. Social Development 1999;8(3):395-411.
  19. McAlister A, Peterson C. A longitudinal study of child siblings and theory of mind development. Cognitive Development 2007;22(2):258-270.
  20. Youngblade LM, Dunn J: Individual differences in young children's pretend play with mother and sibling: Links to relationships and understanding of other people's feelings and beliefs. Child Development 1995;66(5):1472-1492.
  21. de Rosnay M, Hughes C. Conversation and theory of mind: Do children talk their way to socio-cognitive understanding? British Journal of Developmental Psychology 2006;24(1):7-37.
  22. Nelson K. Young minds in social worlds: Experience, meaning and memory. Cambridge, MA: Harvard University Press, 2007.
  23. Milligan KV, Astington JW, Dack LA. Language and theory of mind: Meta-analysis of the relation between language and false-belief understanding. Child Development 2007;78(2):622-646.
  24. Moses LJ, Tahiroglu D. Clarifying the relation between executive function and children’s theories of mind. In: Sokol BW, Müller U, Carpendale JIM, Young A, Iarocci G, eds. Self and social regulation: Social interaction and the development of social understanding and executive functions. New York, NY: Oxford University Press; 2010: 218-233.
  25. Dunn J. Children's relationships: Bridging the divide between cognitive and social development. Journal of Child Psychology and Psychiatry 1996;37(5):507-518.
  26. Astington JW, Jenkins JM. Theory of mind and social understanding. Cognition and Emotion 1995;9(2-3):151-165.
  27. Astington JW: Sometimes necessary, never sufficient: False belief understanding and social competence. In: Repacholi B, Slaughter V, eds. Individual differences in theory of mind: Implications for typical and atypical development. New York, NY: Psychology Press; 2003: 13-38.
  28. Astington JW, Pelletier J. Theory of mind, language, and learning in the early years: Developmental origins of school readiness. In: Homer BD, Tamis-Lemonda CS, eds. The development of social cognition and communication. Mahwah, NJ: Erlbaum; 2005: 205-230.
  29. Sutton J: ToM goes to school: Social cognition and social values in bullying. In: Repacholi B, Slaughter V, eds. Individual differences in theory of mind: Implications for typical and atypical development. New York: Psychology Press; 2003: 99-120.
  30. Baron-Cohen S, Cox A, Baird G, Swettenham J, Nightingale N, Morgan K, Drew A, Charman T. Psychological markers in the detection of autism in infancy in a large population. British Journal of Psychiatry 1996;168:158-163.

Paper financed by the Alberta Centre for Child, Family & Community Research

How to cite this article:

Astington JW, Edward MJ. The Development of Theory of Mind in Early Childhood. In: Tremblay RE, Boivin M, Peters RDeV, eds. Zelazo PD, topic ed. Encyclopedia on Early Childhood Development [online]. Published: August 2010. Accessed July 16, 2024.

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