In friendship as well as love, ignorance very often contributes more … — Francois de La Rochefoucauld

The man of knowledge must be able not only to love his enemies but also to hate his friends. — Friedrich Nietzsche
Even in the common affairs of life, in love, friendship, and marriage, how little security have we when we trust our happiness in the hands of others! — William Hazlitt
Only on paper has humanity yet achieved glory, beauty, truth, knowledge, virtue, and abiding love. — George Bernard Shaw
When a man must force himself to be faithful in his love, this is hardly better than unfaithfulness. — Francois de La Rochefoucauld
Men often pass from love to ambition, but they seldom come back again from ambition to love. — Francois de La Rochefoucauld
Moderation is the feebleness and sloth of the soul, whereas ambition is the warmth and activity of it. — Francois de La Rochefoucauld