Though ambition in itself is a vice, it often is also the parent of virtue.

It is but a step from companionship to slavery when one associates with vice.

Virtue practiced to be seen is not real virtue; vice which fears to be seen is real vice

Virtue by calculation is the virtue of vice

Any virtue taken to the extreme becomes a vice; unfortunately it doesn't work the other way.

A man is fortunate if he encounters living examples of vice, as well as of virtue, to inspire him.