 Hume acknowledges that his second group of natural virtues owes a debt to the Stoic view that a virtuous person ought to be concerned with the welfare of all human beings, whether they be intimate or stranger; and in describing the first group of natural virtues, Hume looks to Socrates as someone who has achieved a kind of inner calm and self-esteem. In addition, his general approach to the natural virtues, that some are based on self-esteem and others on friendly feelings and good will, is reminiscent of Aristotle’s exploration of the psychological foundations of virtue.