Leibniz supported Aquinas in his Principle of Sufficient Reason. He believed that there must be an explanation or reason for everything, and therefore for the existence of the universe. He argues that to say that there is an infinite regress would be saying that the world has no explanation. Science however tells us that everything has an explanation so it is reasonable to assume that the universe has an explanation. He therefore suggests that there can be no infinite regress, so the only explanation for the universe is an unmoved mover and uncaused cause, which he describes as God. Leibniz’s principle strengthens Aquinas argument considerably by making it more conceivable and combating any criticisms.
Another supporter of the Thomist argument is Copleston, who in his radio interview with Russell, argues that there must be an explanation of how things have come into existence, and the universe is not just ‘brute fact,’ as stated by Russell.
There are several weaknesses to the Cosmological Argument, suggested by different philosophers. Hume was the first to find a weakness in the argument. In Dialogues Concerning Natural Religion, he asked why must we conclude that the universe has a beginning: “How can anything that exists from eternity have a cause, since that relation implies a priority in time and in a beginning of existence?” So things that exist from eternity can’t have a cause, otherwise they wont have existed from eternity. Hume continued to say that even if the universe did begin, it does not necessarily mean that anything caused it to come into existence. Because Hume could not believe a connection between cause and effect, proved by his example of a game of billiards, he went on to say that causation is not a physical connection but just an association in our minds.
Another opponent of the argument was Kant. He argued that only events, with which we have experience, have a cause. God is metaphysical, and therefore the argument is invalid as it is impossible for us to have knowledge of him/her and what he/she created.
Russell said, “the universe is just there and that’s all there is to it,” so why does it have to have a cause? He argued that we don’t know if everything has a sufficient reason, as “just because humans have a mother it does not mean that the universe had to have a mother.” If this is true, then the argument provides very little evidence to suggest the existence of God.
Kenny criticised Aquinas’ argument, and claimed that animals and humans can move themselves. He explained that Newton’s law of motion states that movement can be explained by the body’s own inertia from previous motion. This disproves Aquinas’ First Way of motion.
The Big Bang theory provides a scientific explanation for the existence of the universe. This can be used for or against the Thomist argument, depending on whether the cause of the Big Bang was natural or divine. Smith used Quantum Physics to demonstrate that it’s possible for things to be self-causing, so the universe could exist without a direct cause.
One of the main weaknesses to the Cosmological Argument is that it is self-contradictory. Aquinas contradicts himself when he rejects the possibility of the universe being infinite; yet later argues that God is infinite. He also states that everything is contingent, yet God is non-contingent. So who created God? Supporters of the argument would argue that God is unique so the laws of nature do not apply to God.
Although the argument doesn’t point to the classical theism of God; whether or not someone believes in the cosmological argument depends on the faith that they already have. The argument will appear more convincing to the theist who already believes in a God, than the atheist who does not. Faith is needed for a belief in God, as his/her existence cannot be proved by reason alone.
The Kalam Argument is another version of the Cosmological Argument because it also seeks to prove that God was the first cause of the universe.
The Muslim scholars, al-Kindi and al-Ghazali, propounded the Kalam Argument, however William Lane Craig and Ed Miller have since developed the argument.
They both use the idea of actual infinite, as opposed to potential infinite. A potential infinite can be defined as existing if it is always possible to add one more to a series of things or events, e.g. it is possible to think of the future as a potential infinite because more events are always being added to history. Actual infinite is a mathematical concept found in set theory. It refers to sets or collections of things with an infinite number of members. It is not growing towards infinity because it is already infinite. A part within an actually infinite set is equal to the whole set because it is infinite.
Craig stated that the present wouldn’t exist in an actual infinite universe, so as it does exist, the universe must be finite. A finite universe therefore needs a beginning, and a first cause, as things can't cause themselves. This first cause must be God.
Ed Miller argued that an infinite universe would have an infinite number of days and that infinite number of days cannot be reached, so today would never arrive. However today has arrived, so the past cannot be infinite. He went on to argue that time began when the universe began, and events are caused, therefore the beginning of the universe was an event. He concluded that there must have been a first cause, and that the first cause was God.
This argument is different to the Thomist Argument, as it is A Priori. An a Priori argument is defined as a knowledge, which has its justification independent of experience. Although A Priori arguments are not based on actual evidence, they do follow logical steps, so the conclusion is said to be analytically correct. A Priori arguments are also said to be deductive, as they make their conclusion from available information, therefore it is not necessary to have experience of the situation.
The concept of actual infinity, in my opinion, is illogical; so to believe the Kalam argument for the existence of God, you need to understand and agree with this theory.
Like Aquinas, Craig contradicts himself when talking about everything being contingent and being caused by something else, yet stating God is non-contingent and is the First Causer and Mover.
Both the Thomist argument and the Kalam argument start from the existence of the universe to try to prove from this the existence of God. The arguments only succeed if one is willing to question ‘why is there a universe?’ because such a curiosity leads to a logical conclusion of God.
The Thomist argument is a posteriori, which has the advantage that it is based on evidence and experience. Empiricists would support this argument as it uses empirical data, which can be sensed and typically tested. This adds to the strength of the argument, as any experiment with evidence to support the hypothesis, is scientifically classed as reliable. It is more difficult to challenge facts backed with evidence. However, evidence may be misleading, giving an anamolous result that may change over time. The Kalam argument is a priori, so is not dependent on evidence or experience. It only leads to an apparent logical conclusion, and this depends on whether we accept that the premises are analytically true.
Contrasting to the deductive Kalam argument, Aquinas uses induction to prove the existence of God. Induction can be defined as a method of reasoning where a conclusion is reached by linking observations of cause and effect. So given the truth of the premises, it is highly probable that the conclusion of the existence of God is true. Unlike deductive arguments, inductively valid arguments have conclusions that go beyond the claims made by their premises.
I believe that the concept of actual infinite used in the Kalam argument is illogical, however potential infinite used by Aquinas is a simple and easily comprehensible concept.
Sally McFague suggests a strength of the Thomist cosmological argument in her analogy of buckets. She suggests that if a bucket containing a hole is put inside another bucket with a hole, the bucket is strengthened. So on its own, one of Aquinas’ Five Ways can neither prove or disprove the existence of God, yet with the other two Ways the argument can be strengthened.
Overall, the Cosmological Argument is a reasonable argument, but because of the objections and flaws, and although it is evident that it points towards the idea of God, neither the Thomist nor the Kalam arguments create a proof that God exists.
Bibliography
Philosophy of Religion for A Level – Jordan, Lockyer & Tate
The Puzzle of God – Peter Vardy
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