We investigated children's understanding that visual perception is subjective and not alterable by propositional information. Thirty-six children (3.4 to 6.8 years) were tested in a screen condition (in which a puppet views a colored toy through a differently colored screen), and a colorblind condition in which a puppet (introduced as colorblind) looks directly at the toy. Asked to name the color of the object that the puppet sees, children under four fail in both conditions, revealing difficulty grasping false perception. The puppet was then told the correct color of the toy by E, and the child was again asked to name the color the puppet sees. Even the oldest children failed this question in the colorblind condition, revealing the misconception that a label can alter a color's perception. Children as old as six do not understand that although verbal information is an originator of belief, it cannot alter perception.

Key words: theory-of-mind, understanding visual perception