Descartes’ Circle Debunked

Almost since Descartes published his book Meditations he has been accused of committing a fallacy of circular reasoning with his argument that God is the guarantor of the truth of our belief in an external world. Descartes’ argument has ever since been derided as the “Cartesian Circle.” The argument against the so-called “Cartesian Circle” is actually a fallacious strawman argument that misrepresents what Descartes actually argues.

The accusation against Descartes is that he asserts that the existence of God verifies that ideas that are clear and distinct must be true. So those who argue the “Cartesian Circle” position are claiming that Descartes is arguing the following:

    1. I have a clear and distinct idea of God as a perfect being.
    2. God, a perfect being, is not a deceiver and would not allow me to be mistaken about my clear and distinct ideas.
    3. Therefore, I can be certain of the truth of my clear and distinct ideas.

As the Encyclopedia Britannica states it (I think a reasonable summation of the standard interpretation of the Cartesian Circle):

But Descartes cannot know that this proof does not contain an error unless he assumes that his clear and distinct perception of the steps of his reasoning guarantees that the proof is correct. Thus the criterion of clear and distinct perception depends on the assumption that God exists, which in turn depends on the criterion of clear and distinct perception.

This is a valid assessment of the argument stated above. The question though is whether that is an accurate portrayal of Descartes’ actual argument.

Garret Thomson in Bacon to Kant argues that it is not. The key to understanding Descartes’ argument is to discern the difference between particular experiences and the whole of experience.

Descartes uses the proposition “Ideas that are clear and distinct must be true” as his foundational principle. All else follows from that. The proposition is true independent of God. Any idea that can be said to be clear and distinct then must be accepted as true. The existence of God is not a “that X” proposition, it is a clear and distinct idea, God cannot be doubted. The existence of God does not support the proposition “Ideas that are clear and distinct must be true” it guarantees that our sensory perception is trustworthy, or as Thomson puts it on p. 35, “God is introduced to meet our general systematic doubts.” We can, as Descartes points out, doubt that the external world exists; we could be deceived. God ensures that we are not deceived because God is not a deceiver.

So, Descartes’ reasoning goes like this:

    1. Ideas that are clear and distinct must be true
    2. I have a clear and distinct idea of God
    3. Therefore, God must exist.
    4. Since my idea of God includes his perfection, God is trustworthy
    5. Therefore, I cannot be deceived about the existence of the external world because God would not allow me to be deceived.

Descartes is not saying that he cannot be mistaken about particular propositions such as “that X” because he knows his will can overreach and lead him to error. But because he knows he is a mind and because he knows God would not let him be deceived, then knowledge from experience is possible. Thus, if he can reason correctly (his four rules of scientific method) then his mind is incapable of error because he can arrive at clear and distinct ideas.

Descartes’s reasoning can be questioned in several of its premises, but it is not circular reasoning. The accusation of the “Cartesian Circle” is a fallacious strawman argument.

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We See What We Want to See

The human mind is incredible, capable of amazing feats. But it is not perfect as philosophers have known since before Socrates. The senses can be fooled because of their physical limitations but a much more destructive force is the mind’s ability to be warped by its own desires. We see sometimes what we want to see and will make our selves see, or not see, what suits our prejudices.

I found vivid evidence of this when I ran across a site interesting in how utterly whacked out it is. The site is quite entertaining really. It makes the claim that “Phobos — from this wondrous visual evidence alone — IS unquestionably ‘an ancient, artificial moon’ …. an ET space ship!” Uh… not so much. Look at the photos for yourself. I don’t see anything artificial and I certainly don’t see the spaceship features the author keeps talking about. I strongly suspect you won’t either. Even if we are charitable to the author, his assertion that the evidence is “unquestionable” is quite questionable.

Which leaves us with two possibilities about our author. He is lying in order to sell us something or he is delusional. Admitting the very real possibility of the former, I suspect more the latter. There is a segment of the population that seems to sincerely believe in tall tales because they want to believe them. That’s part of the human condition and everyone–yes everyone, me and you too–sees what they want to see. Hopefully not things as delusional as seeing alien spaceships in moons of other planets. As Francis Bacon once said, when we find ourselves liking an idea we should question ourselves as to whether we are believing it because we like it or if there really is a rational reason to hold that belief.

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On Religion and Ethics

Blame religion? That’s too easy and too wrong. Just as people don’t need religion to be ethical, they don’t need religion to be unethical. Religion never created any saints or monsters – the saints and monsters created themselves.

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The Other and Wisdom

To be able to imagine the other, and the experience of the other, was what wisdom was all about.

– Alexander McCall Smith


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The Meaning of Heresy

The word “heretic” has become synonymous with unorthodox with an insinuation of cult-like behavior. But look at the etymology of the word:

HERESY – “In ancient Greek, the verb ‘hairein,’ meaning ‘to take,’ gave rise to the adjective ‘hairetos’ ‘able to choose’ and the noun ‘hairesis’ ‘the act of choosing.’ In time the noun developed the extended senses of ‘a choice,’ ‘a course of action,’ ‘a school of thought,’ and ‘a philosophical or religious sect.’ Stoicism, for example, was a ‘hairesis.’

So a heretic is someone who makes a choice, and heresy is a belief or action that is chosen. Originally the term was not pejorative though it did become that when wielded by a group that called themselves The Apostolic Church (community). Beginning around the start of the first century CE, the group, claiming to know the pure teaching of the twelve apostles of Jesus, began to use the term ‘hairesis’ for other beliefs about Jesus. The word ‘hairesis’ was appropriate because the Apostolic position was that their doctrines were the original Christian teachings and all who disagreed had chosen a contrary (and thus erroneous) doctrine. The Apostolic Church’s chief opponent was the Marcionite Church (after its founder Marcion) which taught that Jesus was sent by a different god than the god known as Yahweh and believed that they were the true followers of Jesus’s teachings. An intellectual battle between the Marcionite and Apostolic churches lasted for several centuries and the Apostolic Church prevailed. Since history is written by the winners, the Marcionites were declared “heretics” and condemned as not just people who chose a school of thought but people who choose an evil path.

The Apostolic Church was the forerunner of the Catholic Church, which claimed the Apostolic doctrinal authority. The latter inherited the habit of declaring doctrinal opponents “heretics” and the model of dealing with heretics. As the centuries past the methods of dealing with heretics evolved leading to official intolerance, excommunication, and the Inquisition.

It is important to realize that heresy begins with a choice – a choice to think for one’s self. And intellectual freedom is not often accepted by the powers that be – then and now.

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