Descartes’ Special Causal Principle
In his Meditations, Rene Descartes attempts to uncover certain truths about existence. In his Third Meditation, he establishes his "special causal principle" (SCP). Descartes uses this principle to explore the origin of ideas, and to prove the existence of God. I agree that there is much logic to be found in the SCP, but I disagree with Descartes method of proving God's existence, and in this essay I will explain why. I will begin by explaining the SCP, and will then demonstrate how Descartes applies this principle to prove that God exists. I will then present my critique of the SCP, and expose the flaws in both of Descartes proofs with regards to the principle. A conclusion will then follow.
In Descartes Second Meditation, he established that because he is a thinking being, he exists. In the Third Meditation, Descartes attempts to build upon this foundation by questioning whether or not anything exists outside of him. In order to do so, he must distinguish between those of his thoughts that come from outside, and those which only seem to. The method Descartes uses for this differentiation is the special causal principle (SCP). At its core, the SCP is a basic cause and effect argument. Descartes begins his rationale for the SCP as follows:
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.1
There are two major outcomes of this logic. Firstly, that something cannot come from nothing, and secondly that what contains more reality (or is more perfect) cannot come from something that contains less reality (or is less perfect). To illustrate this argument, Descartes uses the example of a stone. He notes that "a stone cannot begin to exist"2 unless it is produced by something which contains every quality which the stone possesses. Newton's laws of motion dictate that an object remains inert unless it is acted upon by some force. It follows that the effect of that force cannot be greater than the force itself. For example, a boy scout cannot derive more heat from a campfire than the actual temperature of the fire itself. As far as physical objects go, Descartes is making a completely logical argument.
At this point, we must remember that Descartes' is still dealing with the metaphysical. He has yet to prove that anything in the physical world exists. Descartes avoids this trap by formulating that the SCP not only applies to physical objects, but also to ideas. By applying the SCP to his ideas (which exist metaphysically), Descartes is providing himself with his sole criteria to judge between true existence and existence that is merely perceived. In order to show that ideas are subject to the SCP, Descartes points out a difference between formal and objective reality. Objective reality is the reality presented in a picture or idea, whereas...