Abstract

Appropriate philosophical language for describing the nature of God took almost two millennia to develop. Parmenides first discovered the language of being. Plato then distinguished the world of changing beings from the world of true being and also from the good “beyond being.” He refused to use being language for the Olympic gods. Aristotle understood a god as a substance (oujsiva). Avicenna described God, not as a substance but as “being,” which transcends thecategories, including substance. For Br. Thomas of Aquino, God was no longer an Aristotelian substance, nor even an Avicennian “necessary being,” but is bestdescribed as “subsistent being itself ” (ipsum esse subsistens). Here the Christian disciple brought to an even higher level of perfection the achievements of his Islamic master, achievements that far surpassed their beginnings in Parmenidean monism.