Trademark argument

The trademark argument is an a priori argument for the existence of God developed by French philosopher and mathematician, René Descartes.

In the Meditations Descartes provides two arguments for the existence of God. In Meditation V he presents a version of the ontological argument which attempts to deduce the existence of God from the nature of God; in Meditation III he presents an argument for the existence of God from one of the effects of God’s activity. Descartes cannot start with the existence of the world or with some feature of the world for, at this stage of his argument, he hasn’t established that the world exists. Instead, he starts with the fact that he has an idea of God and concludes “that the mere fact that I exist and have within me an idea of a most perfect being, that is, God, provides a very clear proof that God indeed exists.” He says, “it is no surprise that God, in creating me, should have placed this idea in me to be, as it were, the mark of the craftsman stamped on his work.”

To understand Descartes’ argument it is necessary to understand some of the metaphysical assumptions that Descartes is using.

Descartes says,

“Undoubtedly, the ideas which represent substances to me amount to something more and, so to speak, contain within themselves more objective reality than the ideas which merely represent modes or accidents. Again, the idea that gives me my understanding of a supreme God…certainly has in it more objective reality than the ideas that represent finite substances. Now it is manifest by the natural light that there must be at least as much reality in the efficient and total cause as in the effect of that cause. For where, I ask, could the effect get its reality from, if not from the cause? And how could the cause give it to the effect unless it possessed it? It follows from this both that something cannot arise from nothing, and also that what is more perfect—that is, contains in itself more reality—cannot arise from what is less perfect.”

Descartes goes on to describe this as ‘transparently true’. Commenting on this passage Williams says, “This is a piece of scholastic metaphysics, and it is one of the most striking indications of the historical gap that exists between Descartes’s thought and our own, despite the modern reality of much else that he writes, that he can unblinkingly accept this unintuitive and barely comprehensible principle as self-evident in the light of reason.”

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