It is exercise alone that supports the spirits, and keeps the mind in vigor.
The process, indeed, of nature is this: that just in the same manner as our birth was the beginning of things with us, so death will be the end; and as we were noways concerned with anything before we were born, so neither shall we be after we are dead.
O philosophy, life's guide! O searcher-out of virtue and expeller of vices! What could we and every age of men have been without thee? Thou hast produced cities; thou hast called men scattered about into the social enjoyment of life.
As I give thought to the matter, I find four causes for the apparent misery of old age; first it withdraws us from active accomplishments; second, it renders the body less powerful; third, it deprives us of almost all forms of enjoyment; fourth, it stands not far from death.