The soul languishing in obscurity contracts a kind of rust, or abandons itself to the chimera of presumption; for it is natural for it to acquire something, even when separated from any one.

Vain hopes are like certain dreams of those who wake.

We excuse our sloth under the pretext of difficulty.

Ambition is a vice, but it may be the father of virtue.

Consequently the student who is devoid of talent will derive no more profit from this work than barren soil from a treatise on agriculture.

Without natural gifts technical rules are useless.

Fear of the future is worse than one's present fortune.