Aquinas on Matter

Natural forms imply properties that express themselves through predictable outcomes or effects of the natural form. Even so far as these effects follow from or flow from the kind of reality in question we may speak of teleology or final causality. In interpreting Aquinas on matter it is helpful from the start to make a basic distinction. The word matter can be taken in two ways: First, there are material parts of natural forms; and second, there is matter as pure potency, so-called prime matter.