The existence of god. (Apologetics).

In Catholic high schools and colleges several decades ago, there was a course in the Theology Department called apologetics. The word is from the Greek meaning defence. Such a course is a defence of the rationality, the reasonableness, of Catholicism. It shows that many revealed truths can be proven by philosophy also, without direct aid from revelation. And it shows that other revealed truths, though not provable by philosophy, do not contradict it, and are eminently acceptable by many philosophers as reasonable.

Some of the chief areas of apologetics deal with the existence of God, the nature of God, the immortality of the human soul, and the reasonableness of revealed truths. We might begin here with the existence of God.

Philosophers unaffected by Jewish or Christian revelation (for example, Plato and Aristotle), contended that there were gods. When Jews and Christians began to philosophize they knew that, though many philosophers accepted the existence of gods, the gods they had in mind were quite different from the Christian God. The gods of the pagan philosophers were many in number; many of them had weaknesses; and not one of them was a creating God. These Jewish and Christian philosophers also realized that the God of Christianity was eminently superior to all other contending divinities, and more reasonable than any of them. Several of these philosophers claimed that they could prove the existence of a creating God.

It is widely recognized that, in this matter, the greatest of the Catholic theologians who was also a philosopher was St. Thomas Aquinas (1225-1274). He knew that the reason the pagan philosophers taught that there were gods was that certain aspects of the world in which we live were more readily explained if this teaching was held. For example, every normal person develops a conscience, which makes intellectual judgments that some actions are good and others are evil, and that we experience an obligation to obey these judgments; therefore, they argued, there must be someone in charge of the moral order to enforce laws or punish transgressions, or else conscience is an illusion.

Though this argument appealed to some thinkers like Cardinal John Henry Newman, Aquinas doesn't adopt it, perhaps because, like the psychologist Sigmund Freud, some philosophers might say that yes, conscience is an illusion. Aquinas looks for arguments which allow no such escape.

One necessary being

Aquinas is able to show that, since at least one being exists, there is at least one necessary being, one being which must exist. The things which we usually meet are not necessary beings, because they come and go; a necessary being must exist and therefore must always exist. If all beings were contingent (that is, not necessary), nothing would exist, because there would be no cause to bring into existence beings which of themselves do not exist, since a contingent being requires a cause for its existence. This is true even in an infinite time span and in the case of an infinite multiplicity of contingent beings, because, no matter how many contingent beings one might consider, none would exist without a necessary being, just as, in the case of a watch with many wheels, since wheels do not move themselves, there would be no motion without a spring, even if the multiplicity of wheels was infinite and they had an eternal existence (Summa Theologica, I, 2, 3).

We are not able here to consider Aquinas' full arguments for the existence of a single creating God because these arguments are complex and very difficult. But we might mention that, since God is the creator of everything that is not God, God must be an infinite act of existing since He is able to impart existence to contingent beings. For the first time in the history of philosophy, Aquinas taught that the existence of something is not just a fact, but that it is an act, and that the first activity of anything which exists is its act of existing. Creation is the act of producing something which previously did not exist but now is activated by an act of existing. And, since God has such power, He must have an infinite act of existing. This means that, in a contingent being its act of existing is limited by its nature, whereas in God it is unlimited; that is, it is infinite. God's very nature is an infinite act of existing. This act is not limited by God's nature but is identical with His nature (Summa Theolo gica, I, 3, 4).

Father Kennedy has taught the philosophy of Thomas Aquinas at several universities.

In the beginning was the Word, the Word was with God, and the Word was God.

John I