Cartesian circle, Was Descartes' logic circular

     The Cartesian Circle is a claim that argues the Cartesian argument about existence of clear and distinct ideas are dependent on existence of God is circular. I argue that the claim is wrong and therefore, Descartes’s argument is not circular because we don’t need to know that God exists for saying that our clear and distinct perceptions are true (psychologically certain). But to say that our memory is trustable and more importantly our clear perceptions are objectively true beyond our perception, we need to say that God exists.

The Cartesian circle is a claim that follows:

1.     Descartes argues that clear and distinct ideas are true only if God exists and is not a deceiver.

2.     To know that God exists, I need to say that clear and distinct ideas are true

So, they claim there is a circularity between these propositions. The famous response to the claim from Descartes is rejecting 1 in reply to objections (146): He does not argue that clear and distinct ideas are not certain, so God does not guarantee these ideas, but he guarantees my c&d memories.

  Let’s suppose that an atheist is solving a problem about a triangle and to solve the problem he needs to remember that he c&d perceived three angles of a triangle equals to two right angles, he cannot say that “oh! I remember that three angles are equal to two right angles” because without the existence of God he cannot be sure if his memory is correct.

1.     I remember that I c&d perceived three angles of a triangle is equal to two right angles(p)

2.     My memory is trustable therefore I can say that I did perceive p

C: I clearly and distinctly perceive that three angles of a triangle is equal to two right angles

Descartes rejects the second premise. He thinks that second premise is true only if God exists. It actually means that science and even mathematics is impossible for Atheists. Because they always have to question their memory.

 An objector can argue that we use memory to prove God. Suppose that an argument goes like this: S entailed Q, Q entailed p then at last p entailed r. But when we reach r, don’t we need to remember c&d perception of S to prove r; if this is the case proving existence of God is impossible. Willis Doney thinks that Descartes states, after the reaching r, we can see that there is a necessary connection between s-q-p-r and they all are present in the mind at the same time(328). And that clearly shows we don’t need to use memory to know something present in mind.

     So, it seems that we get rid of the problem but it is not easy as much. Descartes thinks that our c&d perceptions are open to doubt. Descartes in the 35. Paragraph of meditations(4. Paragraph of 3. Meditation) says that even my clear and distinct perception of 3+2=5 is open to doubt because an evil genius can trick us into thinking so. What Descartes and many philosophers think that to say that c&d perception is objectively true, we need an all-good God. This shows that Cartesian doubt includes our clear and distinct ideas. Descartes, for one, is a radical doubter. For Descartes, we don’t need to perceive the doubt but we just need to say that the doubt is epistemically possible. So, without perceiving that our doubt is clearly and distinctly wrong, we cannot say that our perception is objectively true. But firstly, we need to talk about the difference between psychological certainty and metaphysical(normative) certainty. Psychological certainty is our subjective certainty and it forces us to believe it. On the other hand, metaphysical certainty includes objectiveness and it means p is real beyond myself and my perception. Alan Gewirth argues that God guarantees only metaphysical certainty and if this is the case we can say that there is no circle(372). I think Gewirth is right and Descartes was aware of it and he thought that even the c&d perceptions are just psychologically certain until we prove that God exists and his veracity makes what we are psychologically certain, metaphysically certain. What I think, Descartes argues that “I think therefore I am” is not objective truth until the 4. Meditation that he understood that God exists and is not a deceiver. So, in the beginning there was just psychological certainty of my existence and some other c&d perceptions that Descartes used to show the existence of God, and they were just psychologically certain, so, they were still open to doubt. But after we concluded that God is not a deceiver, we can claim our c&d perceptions are metaphysically certain. So, we get rid of the circle by saying that what Descartes mean c&d perception is psychological certainty. On the other hand, he claims that they did not have metaphysical certainty until God’s veracity made all c&d perceptions metaphysically certain. So, as I mentioned we reject (1) and say that we don’t need God to say that c&d ideas are true. But it was just in psychological sense. Here we say that we reject (2) and concluded that God is essential to say that c&d perceptions are true and it is just in metaphysical sense. But does not mean that we are not certain of c&d ideas are true without God(Q). We are certain but we are not certain of Q. 

1. If c&d ideas are objectively certain, there must be no epistemically possible doubt

2. Only if God exists and he is a not a deceiver, doubt is epistemically impossible

3. God is not a deceiver

C: All c&d ideas are objectively true

We said that radical doubt leads to him to doubt his c&d perceptions that are psychologically certain. But why do we doubt them, radical doubt only includes ideas that are open to doubt but is the cogito argument open to doubt? James Van Cleve argues in his essay that Cartesian doubt does not need certainty, so we don’t need to c&d perceive the doubt itself (63). Cartesian doubt still exists because even doubting cogito is epistemically possible. In his argument, he says that I can think a scenario that a proposition is evident to me and Demon hypothesis is true, it means p is false. So, it is epistemically possible to say that I can doubt the psychological certainty. As a result, theists have one more advantage than atheists. Like memory, when theists are certain of the truth of propositions of their c&d perceptions whereas atheists are not. Even if Atheists are certain that they exist(S), the proposition is still open to doubt.

But there can be big objection: We said that psychological certainties are open to doubt but we proved the existence of God with these ideas. It seems there is still a circularity, we have to say that c&d ideas are not open to doubt (metaphysically certain) to say that God exists. But as I mentioned I did not say that I am not certain of c&d perceptions are true (Q) but I am in doubt whether Q is true because as I showed in the previous paragraph the propositions of c&d ideas are true, is still in doubt. Van Cleve argues that we don’t have to say that these propositions are close to doubt; until we can say that clear and distinct perceptions are true, we can still conclude that God exists (67). So, he uses these ideas as a knowledge maker. Descartes uses clear and distinct ideas as impossible to not believe in them. Therefore, we cannot say that c&d ideas are uncertain therefore we can use them to prove God.

To sum up, we have shown that cartesian circle is not a real circle. When Descartes argues that truth of our c&d perception dependent of God who is not a deceiver, he means not psychological certainty but metaphysical certainty. Furthermore, he thinks that c&d perceptions are psychologically certain for all people but only theists can trust their memories therefore psychological certainty of clear and distinct perceptions about past exists only if we believe in God who is not a deceiver.

Works Cited

Doney, Willis. “The Cartesian Circle.” Journal of the History of Ideas, vol. 16, no. 3, 1955, pp. 324–338. JSTOR, www.jstor.org/stable/2707635.

Gewirtz, Alan. “The Cartesian Circle.” The Philosophical Review, vol. 50, no. 4, 1941, pp. 368–395. JSTOR, www.jstor.org/stable/2181069.

Cleve, James Van. “Foundationalism, Epistemic Principles, and the Cartesian Circle.” The Philosophical Review, vol. 88, no. 1, 1979, pp. 55–55., doi:10.2307/2184779.