"No great genius has ever existed without some touch of madness."

Anybody can become angry - that is easy; but to be angry with the right person, and to the right degree, and at the right time, and for the right purpose, and in the right way - that is not within everybody's power and is not easy.

The roots of education are bitter, but the fruit is sweet.

Friendship is a single soul dwelling in two bodies.

What is a friend? A single soul dwelling in two bodies.

. . . happiness is the highest good, being a realization and perfect practice of virtue, which some can attain, while others have little or none of it. . . .

Men regard it as their right to return evil for evil - and if they cannot, feel they have lost their liberty.

The best friend is the man who in wishing me well wishes it for my sake.

Misfortune shows those who are not really friends.

Our best friends and our worst enemies are our thoughts. A thought can do us more good than a doctor or a banker or a faithful friend. It can also do us more harm than a brick.