On Rewards and Punishments (17-18)

and by this enigmatical expression the two things are clearly intimated, the migration by the change of place, and the solitude by his not being found. And very appropriately is this stated; for if in real truth man had resolved at all times to show himself really superior to the passions, despising all pleasures and all appetites, then he would require to prepare himself diligently, fleeing without ever turning his head round, and forsaking his home, and his country, and his relations, and his friends;

for familiar custom is an attractive thing, so that there is reason to fear that if a man remains behind he may be taken prisoner, being caught by such powerful charms all round, the appearances of which will again rouse up the disgraceful though at present dormant appetites for evil pursuits, and will restore to vitality those recollections which it was creditable to have forgotten.