Oh the Greeks had the concept, yes, but Aquinas' knowledge was
   limited to Aristotle for the most part, thanks to his teacher,
   Albertus Magnus being the first to provide a commentary on
   Aristotle in the new University of Padua, founded in 1222. But
   many of the other works of the ancient greeks weren't seen by
   Western Scholars until Gemistus Pletho was brought in from the
   Byzantines to attend the failed Council of Florence. That
   sparked the new wave of neoplatonism (now they had Plato and
   others) and REALLY began the wave of humanism from there,
   science, rationalism, and whatever followed 'til today. Hence, I
   start with Aquinas for modern viewpoint because he's: a) Well
   known. b) started his work while much of the knowledge of the
   ancients were simply unavailable to him. Mind you, I'm not
   knocking the excellent efforts of the early University system
   and Scholasticism: They worked with what they had. But it set a
   way-of-thinking into motion that led on a path to today.