One citizen differs from another, but the salvation of the community is the common business of them all. This community is the constitution; the virtue of the citizen must therefore be relative to the constitution of which he is a member.

The soul is the form of the body

Learning is not child's play; we cannot learn without pain.

We are what we continually do.

Philosophy begins with wonder.

Men in general desire the good and not merely what their fathers had.

The seat of the soul and the control of voluntary movement - in fact, of nervous functions in general, - are to be sought in the heart. The brain is an organ of minor importance.