As I considered the matter carefully it gradually came to light that all those matters only were referred to mathematics in which order and measurements are investigated, and that it makes no difference whether it be in numbers, figures, stars, sounds or any other object that the question of measurement arises. I saw consequently that there must be some general science to explain that element as a whole which gives rise to problems about order and measurement, restricted as these are to no special subject matter. This, I perceived was called 'universal mathematics'.
Rene DescartesThe mind effortlessly and automatically takes in new ideas, which remain in limbo until verified or rejected by conscious, rational analysis.
Rene DescartesEvery man is indeed bound to do what he can to promote the good of others, and a man who is of no use to anyone is strictly worthless.
Rene DescartesA person has two passions for love and abhorrence. A big disposition to excessiveness has just a love, because it is more ardent and stronger.
Rene DescartesBe that as it may, there is fixed in my mind a certain opinion of long standing, namely that there exists a God who is able to do anything and by whom I, such as I am, have been created. How do I know that he did not bring it about that there is no earth at all, no heavens, no extended thing, no shape, no size, no place, and yet bringing it about that all these things appear to me to exist precisely as they do now?
Rene DescartesHere I beg you to observe in passing that the scruples that prevented ancient writers from using arithmetical terms in geometry, and which can only be a consequence of their inability to perceive clearly the relation between these two subjects, introduced much obscurity and confusion into their explanations.
Rene Descartes