Date: 1644, 1647

"The brute beasts, who have only their bodies to preserve, are continually occupied in looking for food to nourish them; but human beings, whose most important part is the mind, should devote their main efforts to the search for wisdom, which is the true food of the mind."

— Descartes, René (1596-1650)

Date: 1644, 1647

A 'clear' perception is analogous to an object "present to the eye's gaze" that "stimulates it with a sufficient degree of strength and accessibility"

— Descartes, René (1596-1650)

Date: 1644, 1647

"But the fact that we feel a pain as it were in our foot does not make it certain that the pain exists outside our mind, in the foot, any more than the fact that we see light as it were in the sun, makes it certain the light exists outside us, in the sun."

— Descartes, René (1596-1650)

Date: 1644, 1647

"In later years the mind is no longer a total slave to the body, and does not refer everything to it."

— Descartes, René (1596-1650)

Date: 1644, 1647

False judgments stick in the memory and are difficult to erase

— Descartes, René (1596-1650)

Date: 1644, 1647

"It must be realized that the human soul, while informing the entire body, nevertheless has its principal seat in the brain."

— Descartes, René (1596-1650)

Date: 1644, 1647

"Sensory awareness comes about by means of nerves, which stretch like threads from the brain to all the limbs, and are joined together in such a way that hardly any part of the human body can be touched without producing movement in several of the nerve-ends that are scattered around in that area"

— Descartes, René (1596-1650)