Where evil habits are once settled, they are more easily broken than mended.

Let us never adopt the maxim, Rather lose our friend than our jest.

Conscience is a thousand witnesses.

A liar should have a good memory.

It is much easier to try one's hand at many things than to concentrate one's powers on one thing.

Study depends on the goodwill of the student, a quality that cannot be secured by compulsion.

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