Theory of mind is the understanding that others have beliefs, desires, and intentions different from one's own. At approximately what age do most children begin to demonstrate this in simple form?

• A. 4-5 years
• B. 2-3 years
• C. 6-7 years
• D. 1-2 years

Answer: (A)

Understanding that other people can hold beliefs different from your own is tested with false-belief understanding. Most children begin to show this in simple form around four to five years old. Before that, around two to three years, they typically assume others know what they know and will act according to reality, not according to someone else’s belief. After four, and more reliably by five, children can predict behavior based on another person’s belief, even if that belief is false. For example, if a toy is hidden and later moved without the other person seeing it, a child around four to five will expect that person to look for the toy where that person believes it to be, not where it actually is. That’s why the four-to-five year range best fits demonstrating this milestone.