Mind: A Brief Introduction (John R. Searle) / quote 22 of 138
We perceive only the contents of our minds
It is important to understand that on Descartes’ view we do not directly perceive objects and states of affairs in the world. What we directly perceive, that is, perceive without any inferential processes, are the contents of our own minds. So if I hold up my hand in front of my face, what I directly perceive, what I strictly and literally perceive, according to Descartes, is a certain visual experience that I am having. Descartes calls these experiences “ideas.” I perceive not the hand in itself, but rather a certain visual representation of the hand, a kind of mental picture of the hand. But then the question arises, How do I know there really is a hand out there on the other side causing me to have this mental picture?