Here 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.

Each problem that I solved became a rule, which served afterwards to solve other problems.

There is nothing so strange and so unbelievable that it has not been said by one philosopher or another.

In order to improve the mind, we ought less to learn, than to contemplate.

A state is better governed which has few laws, and those laws strictly observed.

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'.

The chief cause of human errors is to be found in the prejudices picked up in childhood.