Goodness, perfect

The concept of perfect goodness had a central place in ancient Greek and medieval philosophy, and is still frequently discussed in contemporary natural theology. Medieval philosophers adopted the idea from the philosophies of Plato and Aristotle, with the difference that they identified perfect goodness with a personal God. In ancient and medieval philosophy the concept is primarily a metaphysical one, since goodness was thought to be extensionally equivalent to being, but it is secondarily a moral concept referring to the distinctive sort of goodness appropriate to those beings that have wills. Thus it is fundamental to a long tradition on the metaphysical basis of value which lasted from Plato until at least the sixteenth century.

In Plato, perfect goodness is the Form of the Good, upon which everything that has being is ontologically and causally dependent. In Aristotle, the good is identified with the end or purpose of a natural being. The good is that towards which all things move for the fulfilment of their natures. By the time of Aquinas, medieval philosophers had identified the good in both the Platonic and Aristotelian senses with the Christian God and had argued that God is both the perfectly good creative source and the perfectly good end of all beings other than himself.

The concept of a perfectly good being in Christian philosophical theology faces two major kinds of difficulty. One is the problem that perfect goodness appears to be incompatible with the divine attributes of omnipotence and freedom of the divine will. And if a perfectly good being does not have a will that is free in a morally significant sense, that being seems to lack goodness in the moral sense of goodness. The second kind of problem is that the existence of a being who is both omnipotent and perfectly good seems to be incompatible with the existence of evil. In spite of these problems, there is a strong attraction to the idea of a perfectly good God in contemporary philosophical theology. The category of perfect goodness is therefore one of the most persistent of the concepts in the Platonic legacy.