For just as thou wouldst judge him to be the strongest walker whose legs could carry him to a point beyond which no further advance was possible, so must thou needs account him strong in power who so attains the end of his desires that nothing further to be desired lies beyond.

Whence follows the obvious conclusion that they who are wicked are seen likewise to be wholly destitute of strength.

For why do they forsake virtue and follow vice?
Is it from ignorance of what is good?
Well, what is more weak and feeble than the blindness of ignorance?
Do they know what they ought to follow, but lust drives them aside out of the way?
If it be so, they are still frail by reason of their incontinence, for they cannot fight against vice.

Or do they knowingly and wilfully forsake the good and turn aside to vice?
Why, at this rate, they not only cease to have power, but cease to be at all.

For they who forsake the common end of all things that are, they likewise also cease to be at all.