Paul Tillich, A History Of Christian Thought
Medieval Theology. Thomas Aquinas and Duns Scotus.
We must now go into the main problems of the medieval development. I just finished yesterday by saying that the conf lict between Aristotle and Augustine characterizes the medieval situation. Let me first make clear what Aristotle means for the Middle Ages in the moment in which he was discovered in the beginning of the 13th century, with the help of the Arabic philosophers.
1) Aristotle’s logic was always known, but this was used as a tool and didn’t influence the content of theology directly. When the whole work of Aristotle was rediscovered, it was a complete system in which all realms of life were discussed – observations about nature, about politics, about ethics, an independent secular world-view, including a system of values and meanings. The question was: How could a world which was educated in the Augustinian ecclesiastical tradition deal with this secular system of ideas and meanings? This was the first thing Aristotle meant. It is a little as though theology for centuries asked the question: How can the scientific revolution which has been going on since the 17th century be mediated with the Christian tradition? It was a similar problem for the Middle Ages.
2) Aristotle gave basic metaphysical categories, such as form and matter, actuality and potentiality. He gave a new doctrine of matter, of the relationship of God and the world, and all this on a basis of an ontological analysis of reality.
3) This was perhaps the most important point: He gave a new approach to knowledge. The soul has to receive impressions from the external world. Experience is always the beginning, while in the Augustinian tradition immediate intuition was the beginning. The Augustinians were, so to speak, in the Divine center and judged the world from there. The Aristotelians looked at the world and concluded to the Divine center.
The conclusion, therefore, with which I want to deal first is the question of knowledge. The whole movement of Augustinianism and Aristotelianism must be understood from here. The question was: Is our knowledge a participation in the Divine knowledge of the world and of Himself, or must we, in the opposite way, recognize God by approaching the world from outside? Is God the last or the first in our knowledge? The Augustinians answered: the knowledge of God precedes any other knowledge, it is the first one, we must start with it. In ourselves we have the principles of truth. God is the presupposition even of the question of God, as He is the presupposition of every question for truth. He is, says Bonaventura, the Franciscan Augustinian leader of that time, in the 13th century, “most truly present to the soul and immediately knowable.” The principles of truth are the Divine or the eternal light within us. We start with them. We start with our knowledge of God and we go from there to the world, using the principles of the Divine light which are in us. This Divine light or these principles are the universal categories, especially the so-called “transcendentalia” those things which transcend everything special and given: being, the true, the good, the one: these are ultimate concepts; we have immediate knowledge of them, and this knowledge is the Divine light in our soul.
Only on the basis of this immediate knowledge about the ultimate principles of reality can we find truth in the empirical world. In every act of knowledge these principles are present. Whenever we say “something is so,” whenever we make a logical judgment about something, the ideas of the true, of the good, of being itself, are present; or, as Bonaventura says, “being itself is what first appears in the intellect,” and being itself is the basic statement about God. This means: every act of cognition, every cognitive act, is made in the power of the Divine light, Of this Divine light, of these principles in us, the Franciscans said that it is uncreated; we participate in it. This makes that somehow no secular knowledge exists. All knowledge is in some way rooted in the knowledge of the Divine in us. There is a point of identity in our soul, and this point precedes every special act of knowledge.