Learned men have been wntmg about happiness since antiquity: from Greek times, there is Aristotle's treatise, included in the Nicomachean Ethics; from Roman, Seneca's De Vita Beata. Later came the Christian writings on this subject, especially another De Beata Vita, written by St. Augustine. The point of view is different from Aristotle's or Seneca's but the subject remains the same. In the Middle Ages also treatises on happiness were produced, and these eventually became part of the 'summae'. St. Thomas devoted q. 2-5 of the Prima Secundae to happiness and q. 3 1-39 bear on it indirectly. In...