Kant argued that there were only three kinds of arguments that could be made regarding the existence of some sort of God. He called these the cosmological, ontological, and physico-theological arguments.
Under the cosmological argument type falls all arguments from cause and effect or contingency, arguments to a causa sui which is itself uncaused and unmoved but from whom all cause and movement derive. But this line of argumentation, according to Kant, is relevant only for those convinced that the universe has some reason for its existence, some purpose. But then we are contemplating the nature of the universe as it is in itself and not simply as we perceive it. To move beyond anything tied to perception evaluated by categorical thought, for Kant, is to move into the realm of the unintelligible. This is one of Kant’s antinomies.
The second line of argumentation, from ontology, attempts to argue for God’s existence from the concept or idea of divinity. Anselm’s ontological argument is perhaps the best known example of this form of argumentation. The argument goes like this (quoted from the Internet Encyclopedia of Philosophy):
- It is a conceptual truth (or, so to speak, true by definition) that God is a being than which none greater can be imagined (that is, the greatest possible being that can be imagined).G
- God exists as an idea in the mind.
- A being that exists as an idea in the mind and in reality is, other things being equal, greater than a being that exists only as an idea in the mind.
- Thus, if God exists only as an idea in the mind, then we can imagine something that is greater than God (that is, a greatest possible being that does exist).
- But we cannot imagine something that is greater than God (for it is a contradiction to suppose that we can imagine a being greater than the greatest possible being that can be imagined.)
- Therefore, God exists.
Kant’s criticism is aimed chiefly at premise 3. He argues that existence is not a property of an entity, but a precondition for that entity exhibiting properties. So one cannot argue that “existence” is a property that makes an entity greater than “non-existence,” because it is not in and of itself a property that can make something greater or lesser. The American Philosopher Norman Malcolm puts it like this:
The doctrine that existence is a perfection is remarkably queer. It makes sense and is true to say that my future house will be a better one if it is insulated than if it is not insulated; but what could it mean to say that it will be a better house if it exists than if it does not?
Then there is are the physico-theological arguments. In a nutshell, these are “arguments from design.” This kind of reasoning, Kant wrote…
…always deserves to be mentioned with respect. It is the oldest, the clearest, and the most consonant with human reason. It enlivens the study of nature, just as it itself derives its existence and gains ever new strength from that source. (p.66-67, Scruton)
Scruton, however, defines this line of argument as beginning with “the premiss of some good in nature, and argue(s) by analogy to the perfection of its cause.” (p.66, Scruton) Modern design arguments such as those currently being expounded and propounded by William Dembski, Stephen Meyer and Michael Behe, do not seem have this sort of argument in mind. First, the modern design argument does not proceed from some observable “good” in nature, but rather from particular features of nature. Second, the argument does proceed by analogy to a perfect cause, but rather infers to the best explanation for those particular features of nature.
I infer, for example, that the car sitting in my driveway is not a natural product of the laws of nature but required some intelligence to bring it into existence. But my argument does not depend on whether my car is “good” but rather on its properties. While modern “ID” admits to God as the possible source of the design observed in nature, it does not claim that a “perfect” being must be the source of the design but simply “an intelligence.” Critiques of the modern design hypothesis that refer to the supposed “imperfections” in nature are arguing against Kant’s physico-theological type of argument for the existence of God, and not against the modern concept of intelligent design.
