Date: 1664

"Now among these figures, it is not those imprinted on the external sense organs, or on the internal surface of the brain, which should be taken to be ideas--but only those which are traced in the spirits on the surface of the gland (where the seat of the imagination and the 'common' sense is loc...

— Descartes, René (1596-1650)

Date: 1664

"That is to say, it is only the latter figures which should be taken to be the forms or images which the rational soul united to this machine will consider directly when it imagines some object or perceives it by the senses."

— Descartes, René (1596-1650)

Date: 1664

"But I shall content myself with telling you more about how the traces are imprinted on the internal part of the brain which is the seat of the memory."

— Descartes, René (1596-1650)

Date: 1664

"Thus they also trace figures in these gaps, which correspond to those of the objects. At first they do this less easily and perfectly than they do on gland H, but gradually they do it better and better, as their action becomes stronger and lasts longer, or is repeated more often. That is why the...

— Descartes, René (1596-1650)

Date: 1664

"I should like you to consider, after this, all the functions I have ascribed to this machine -- such as the digestion of food, the beating of the heart and arteries, the nourishment and growth of the limbs, respiration, waking and sleeping, the reception by the external sense organs of light, so...

— Descartes, René (1596-1650)

Date: w. 1628, published in 1684, 1701

"The writers displayed many geometrical truths before my very eyes, as it were, and derived them by means of logical arguments"

— Descartes, René (1596-1650)

Date: w. 1628, published in 1684, 1701

"This is similar to the way in which we know that the last link in a long chain is connected to the first: even if we cannot take in at one glance all the intermediate links on which the connection depends, we can have knowledge of the connection provided we survey the links one after the other, ...

— Descartes, René (1596-1650)

Date: w. 1628, published in 1684, 1701

"For the human mind has within it a sort of spark of the divine, in which the first seeds of useful ways of thinking are sown, seeds which, however neglected and stifled by studies which impede them, often bear fruit of their own accord."

— Descartes, René (1596-1650)

Date: w. 1628, published in 1684, 1701

"But since it is not easy to review all the connections together, and moreover, since our task is not so much to retain them in our memory as to distinguish them with, as it were, the sharp edge of our mind, we must seek a means of developing our intelligence in such a way that we can discern the...

— Descartes, René (1596-1650)

Date: w. 1628, published in 1684, 1701

"We can best learn how mental intuition is to be employed by comparing it with ordinary vision."

— Descartes, René (1596-1650)