Every acquisition, every step forward in knowledge is the result of courage, of severity toward oneself, of cleanliness with respect to oneself.

All sciences are vain and full of errors that are not born of Experience, the mother of all Knowledge.

For, verily, great love springs from great knowledge of the beloved object, and if you little know it, you will be able to love it only little or not at all.

The acquisition of knowledge is always of use to the intellect, because it may thus drive out useless things and retain the good. For nothing can be loved or hated unless it is first known.

All knowledge which ends in words will die as quickly as it came to life, with the exception of the written word: which is its mechanical part.

Abbreviators do harm to knowledge and to love.