Some Criticisms of Aquinas' Cosmological Argument
Created | Updated May 26, 2004
Since Aquinas defined his cosmological argument, many objections have been raised to it, some of which were defined by very prominent philosophers:
See also:
St Thomas Aquinas' Cosmological Argument
The Cosmological Argument in the Kalam Tradition
Infinite Regress
The most obvious objection is to Aquinas’ suggestion that infinite regress cannot exist. This is a major objection in that the unintelligibility of infinite regress was the basis of Aquinas’ presumption of a prime mover. From this can be inferred that either there is an intelligible universe in which a prime mover exists or the universe in unintelligible. This debate on the intelligibility of the universe then extends the argument away from being a proof of God. Various arguments have been made to suggest either view. The steady state theory saw an infinite regress as being perfectly intelligible, and was decidedly atheistic. This theory has been widely discredited, but the alternative big bang theory presents the same problem, as although it argues for a universe with a finite existence and definite beginning, it also allows for the possibility that this universe merely exists as part of an infinite chain of expanding and contracting universes (the Oscillating Universe Theory, originally supported by Stephen Hawking, who later distanced himself from it). Conversely, the philosopher John L. Mackie1 argued that a prime mover was necessary for intelligibility. He uses the analogy of railway carriages. He argues that there can be an infinite number of carriages, each of which may move the next one, but it only makes sense if there is a railway engine. We can see then that the most obvious objection to Aquinas’ theorem greatly damages it, bringing into dispute the basis of the whole argument, for if an infinite regress is possible, then the need for a prime mover is questionable. The objection does not seem to have been sufficiently countered, for even though the steady state theory is in disrepute, the accepted big bang theory still poses the objection, quite possibly magnified. Even Mackie’s argument is of little use, as whilst he defended the argument for a prime mover, he questioned whether Aquinas’ three ways could be related to his analogy.Occam's Razor
Having identified a major flaw in Aquinas’ argument, I shall now look at some of the other objections that have been raised. William of Occam’s simplicity principle, that ‘entities are not to be multiplied beyond necessity’ proves an objection to the argument that cannot be refuted. Occam states that one should stop an explanation at the ‘sufficient condition’ when there is enough information to explain. Anything else is superfluous. As an example, one billiard ball moves because another strikes it. This is the sufficient condition, and to say one billiard ball moves because another strikes it, because that ball was struck by a cue, because that cue was moved by a human, because that human picked up the cue…and to continue back until one reaches God’s prime movement would be superfluous. As simplicity is an inherent necessity of philosophy, Aquinas’ complex chain of causation leaves his argument on indefensible territory.Hume and Causality
David Hume, ever a cynic, argues that causation could merely be an illusion. If the billiard ball moves when another strikes it, that does not necessarily mean that the one caused the other. It is merely psychological that when one ball strikes another, which moves, we assume that there is causation, and not that the ball moved of its own accord, coincidently when the other one struck it. Humean causality would therefore deny the crux of Aquinas’ argument, as if causality is an illusion, then a God derived from it must be so to. This objection is not, however, particularly strong, as it is purely theoretical, and Humean causality is not a widely accepted view, empirical evidence seeming to support the more traditional view, which forms Aquinas’ argument.The Nature of God
Criticism has also been raised concerning the nature of God from the argument. The argument does not prove that there is one prime mover, as there could be numerous chains of causation, each with a different prime mover, intersecting with each other at different points (extending the billiard analogy, imagine two people playing billiards – granted it’s a pretty unrealistic idea). This criticism is not however directed at Aquinas’ argument, just at his decidedly Judaeo-Christian interpretation of the conclusion.Reductionism
The argument of reductionism is also applied, stating that something is no more than the sum of its parts. Aquinas’ argument suggests otherwise, hypothesizing that from the parts, an explanation of the universe can be generated which introduces God, thus making it greater than the sum of its parts. It should, however, be pointed out that while reductionism is a valid argument, religion does tend to reject it as it sees the parts being all that is necessary to create a body, but something greater than the sum makes a person. Since the cosmological argument is evidently religious, reductionism is not therefore altogether relevant.Kant's Critique
One of the most serious criticisms comes from the German Professor of Philosophy Immanuel Kant2. He states that the argument is fundamentally flawed in that it works from empirical evidence (our observations of causality) to non-empirical suggestion (that there is a God). Since the conclusion is outside the boundaries of what we know and have observed, we cannot know if our presumptions from empirical evidence can extend beyond those boundaries, so they cannot support the conclusion, which must therefore be erroneous. This argument draws the distinction between empirical and non-empirical evidence. As it seems logically sound to postulate that the two cannot be reasonably combined, this is therefore a very compelling objection to Aquinas’ theorem.See also:
St Thomas Aquinas' Cosmological Argument
The Cosmological Argument in the Kalam Tradition
