Theory of Mind: The Moment a 4-Year-Old First Understands False Belief
Wimmer & Perner 1983 — when one mind first sees into another
Maxi and the Chocolate Experiment
In Salzburg, 1983, Wimmer and Perner presented a simple puppet show to children aged 3 to 9. The narrative went like this: 'Maxi bought chocolate and put it in kitchen cupboard A. Then he went out to play. His mother came to clean and moved the chocolate to cupboard B. Maxi returned. **Where will Maxi look for the chocolate?**' The correct answer, from an adult's perspective, is A, the place Maxi last saw it. However, a young child's answer often differs significantly from this.
3-Year-Old vs. 5-Year-Old
A 3-year-old confidently answered, 'B!' This is because the child themselves knew the chocolate was in B. They assume that what they know, everyone else also knows. **They cannot distinguish between their own mind and the minds of others.** However, a significant shift occurs rapidly. By age 4, 70% of children begin to answer 'A.' By age 5, 95% answer 'A.' The profound development that unfolds within this short 1-2 year period is known as **Theory of Mind**. It signifies the crucial moment when humans begin to perceive other humans as 'beings with minds,' capable of holding beliefs and intentions different from their own.
Impact of the Discovery
The discovery's impact was profound. In 1985, Simon Baron-Cohen applied a variation of the same experiment, known as the Sally-Anne test, to children on the autism spectrum. The results were striking: the majority of 12-year-old autistic children failed the test, whereas non-autistic 4-year-olds passed. This groundbreaking finding suggested the possibility that the core challenge in autism might not be a general lack of social skills, but rather a **deficit in Theory of Mind**. This hypothesis went on to become the most influential in autism research for the subsequent 40 years. Furthermore, Theory of Mind underpins nearly all social abilities, from understanding deception and empathy to appreciating literature by inferring characters' inner worlds, and even comprehending opposing viewpoints in politics. The continuous development of this capacity, which begins around age 4, is a fundamental aspect of human experience.
The Child in Hanja
The Hanja character '童 (dong)' refers to a young person, originally depicting a child with tied hair. In the Analects of Confucius, Zihan chapter, a profound observation is made: '後生可畏, 焉知來者之不如今也' — 'A youth is to be regarded with awe. How do we know that his future will not be equal to our present?' For Confucius, the significance of '童' lay in the future itself, recognizing the potential of the next generation. What Wimmer and Perner discovered, however, was even more profound. The '童' at age 4 is not simply a smaller version of an adult, but represents the very moment when one human truly discovers another human as a distinct mind. Those crucial 1-2 years, when one mind first connects with another, may well be humanity's most sacred period of development.
