Distrust even Mathematics; albeit so sublime and highly perfected, we have here a machine of such delicacy it can only work in vacuo, and one grain of sand in the wheels is enough to put everything out of gear. One shudders to think to what disaster such a grain of sand may bring a Mathematical brain. Remember Pascal.

Never lend books, for no one ever returns them

What we call strategy is mainly just crossing rivers on bridges and passing mountains though cols.

If fifty million people say a foolish thing, it is still a foolish thing.

You think you are dying for your country; you die for the industrialists.

Jealousy is a virtue of democracies which preserves them from tyrants.

Awaken people's curiosity. It is enough to open minds, do not overload them. Put there just a spark.