Those who are enamoured of practice without science are like a pilot who goes into a ship without rudder or compass and never has any certainty of where he is going. Practice should always be based upon a sound knowledge of theory.

Whoever in debate quotes authority uses not intellect, but memory.

Patience serves as a protection against wrongs as clothes do against cold. For if you put on more clothes as the cold increases, it will have no power to hurt you. So in like manner you must grow in patience when you meet with great wrongs, and they will then be powerless to vex your mind.

As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.

Marriage is like putting your hand into a bag of snakes in the hope of pulling out an eel.

The earth is moved from its position by the weight of a tiny bird resting upon it.

Men of lofty genius when they are doing the least work are most active.