Aquinas uses Aristotle’s research as a basis for his argument. Aristotle looked at nature, and how everything seems to have been caused by an Uncaused Causer, which Aristotle labelled the Prime Mover. When the Western Hemisphere disagreed with Aristotle’s teachings as they did not include the idea of a God, Aquinas combined the teachings of Christianity with Aristotle’s idea of a Prime Mover, stating that God was the Prime Mover. According to Aquinas, God can be known through human rationality, Reason, and divinely revealed truths not available to reason, Revelation.
In his book, ‘Summa Theologiae’, Aquinas outlines his Five Ways, which is calls ‘Demonstratio’. The first three of these ways are about the Cosmological Argument.
The first way focuses on the idea of motion. Aquinas states that anything which is in motion is moved or changed by something else. The object causing this ‘push’ in movement is also given motion by another object. According to Aquinas, infinite regress is logically impossible, and because of this there must be something at the beginning which caused this motion, without being affected itself. This is God.
Aquinas says that God must be an uncaused causer, because if God were the efficient cause, and physically giving the object a ‘push’, rather than being The Final Cause, the ‘push’ would affect God, meaning it would be contingent rather than necessary. To help explain this argument of motion, Aquinas uses the idea of dominoes. One force knocking domino causes the whole line of them to fall. For the objects to go from Potentiality to Actuality there needs to be something in the beginning which has already possessed Actuality.
The second of Aquinas’ ways focuses on causation. He says that everything is a series of causes and effects. For something to have been caused, and effect must have taken place to bring the causes into existence. In the same way, for the effect to take place, it must have had a cause to create the effect. Aquinas states that nothing can cause itself. Just like the first way, Aquinas says there must be something which started the chain of cause and effects, and uncaused cause. This uncaused cause being God. For the same reasons as the first way, God must be The Final Cause rather than the efficient cause.
The third way looks at necessity. Everything is said to be contingent, which means is cannot exist without have been brought into existence without something else. Aquinas shows that infinite regress is impossible, by stating that everything was contingent, then at one point there would have been nothing in existence. This means it would be impossible for the first thing to ever come into existence. Something necessary (needs to exist, and doesn’t rely on anything to exist) must have existed in the beginning to bring the contingent objects into existence. This necessary being is God.
The other man to put forward a different version of the Cosmological Argument was Frederick Copleston. In 1948, Copleston and Russell had a live debate on the radio concerning the universe and the Cosmological Argument. Copleston stated his argument in three different stages: everything within universe has contingency. Because of this, the universe as a whole has got to be contingent. This premise is known as the Fallacy of Composition; jumping from everything within the universe being contingent to the universe itself being contingent. For the contingency of the universe and everything within it to have come into it, a necessary being must have created it. This being is God.
