“The most certain sign of wisdom is cheerfulness. ”

“Stupidity and wisdom meet in the same centre of sentiment and resolution, in the suffering of human accidents.”

“It is only certain that there is nothing certain, and that nothing is more miserable or more proud than man.”

“Learned we may be with another man's learning: we can only be wise with wisdom of our own.”

“It is a disaster that wisdom forbids you to be satisfied with yourself and always sends you away dissatisfied and fearful, whereas stubbornness and foolhardiness fill their hosts with joy and assurance.”

“No wind serves him who addresses his voyage to no certain port.”

“Certainly, if he still has himself, a man of understanding has lost nothing.”