HoP 471 Unclear and Indistinct Ideas: Debating the Meditations
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Hi, I'm Peter Adamson, and you're listening to the History of Philosophy podcast, brought to you with the support of the Philosophy Department at King's College London and the LMU in Munich, online at historyofphilosophy.net. Today's episode, Unclear and Indistinct Ideas, Debating the Meditations.

At the risk of divulging trade secrets and just between us, most academics don't enjoy grading exams. Speaking for myself, it's my least favorite part of the job, admittedly a job I love and am fortunate to have, what with the combination of tedium, time pressure, and the high stakes of needing to evaluate student work fairly. Yet there are moments of genuine pleasure involved too, really excellent papers that stand out, or students who manage to make me laugh out loud.

I particularly cherish the memory of a batch of exams I had many years ago, which were on early modern philosophy. One essay on Thomas Hobbes said that according to him, people in the state of nature were nasty, brutish, and short, a misquotation that conjures up hordes of diminutive prehistoric thugs.

I suspect that was a slip of the pen and not a deliberate joke. But in the same stack of papers, another student was surely going for laughs when they wrote that "Descartes was an expert in geometry which enabled him to argue in a circle." You have to give it to Descartes, actually, a philosopher so famous and influential that even his mistakes have traditional titles. The much-discussed "Cartesian circle" is a supposed flaw in the logic of the meditations.

It's a worry that was put forward by the first readers of the Meditations, including Antoine Arnold. He puts it like this: "Descartes says that we are sure that whatever we perceive clearly and evidently is true, only because God exists. But we can be sure that God exists only because we clearly and distinctly perceive this. Attempts to fend off the charge of circular reasoning go back just as far, with the first attempt being offered by Descartes himself."

Both the problem and solution appear in the "Objections and Replies" that were published along with the meditations itself in 1641, meaning that the work has always been read alongside extensive criticisms with responses from Descartes. These are an invaluable resource for understanding how he took his own arguments to work. Descartes himself initiated the idea by asking Marcin to collect reactions to his treatise.

This was a standing policy on his part. In Discourse on the Method, he also asked for people to send in objections to what he has written. On the one hand, we can see this habit as a holdover from scholastic culture, in which the disputed question was a favorite way of testing arguments. On the other hand, the objections and replies exemplify the intellectual culture of the Republic of Letters. It was of course in a letter that Descartes made his request to Massen, and the objections themselves have an epistolary form.

They each begin with an address to Descartes, which tends to be exaggeratedly polite and complimentary. In these introductions, the critics say that if he could just clear up a few lingering difficulties, his project will stand on firm ground. But once things get serious, the mask of politeness sometimes drops. In all, there are seven sets of objections, two of which were collected together by Mersenne himself.

The other five are by the Dutch theologian Johan de Kutter, the aforementioned Antoine Arnould, Pierre Gossendie, a Jesuit named Pierre Baudin, and none other than Thomas Hobbes, whose criticisms are, appropriately enough, pretty nasty and also short, though certainly not brutish. Picard tends to underestimate the force of Hobbes' brief criticisms, which include some of the most perceptive passages in the Objections.

Gossandie is also insightful and entertainingly sarcastic, too. He teases Descartes for his dualism by addressing him, oh mind. Descartes responds in kind, teasing Gossandie for his materialist proposals by addressing him, oh flesh. The least impressive opponent is probably Baudin.

No doubt some scholar out there would be ready to speak up on his behalf, but I tend to agree with Descartes that Bourdin is long-winded and sometimes pedantic, even if his objections do contain some good points. In the replies, Descartes says numerous times that Bourdin has "misrepresented" or "misunderstood" the arguments in the Meditations, so that his attacks miss their target. This was a disappointment to Descartes, who had asked specifically that a representative of the Jesuit order react to the Meditations.

He wanted to persuade the scholastics with his new ideas, as we also see from the prefatory appeal to the Sorbonne that begins the meditations itself. So he's quite annoyed that the Jesuit who was willing to enter the fray is such a non-entity. All this is entirely typical of the Republic of Letters, with intellectual posturing and point scoring framed by polite declarations of admiration and respect.

The upshot is that we have an abundance of additional material to work with here, beyond the meditations itself. In the translation I've been using, the six chapters of the meditations are a tidy 50 pages or so, whereas the objections and replies span more than 300 pages.

These cover a number of points we've already discussed: the fact that the skeptical arguments in Cogito are derivative, already to be found in Augustine and other authors; the difficulty of giving a purely mechanical account for physiological processes, or of accounting for the interaction of mind and body; the prospect of God making impossible things turn out to be true; the worry that skepticism cannot be defeated, and that we can only ever be sure that things seem to us to be a certain way.

In the episode on dualism, I mentioned the problem that even if Descartes can doubt the existence of his body while not doubting the existence of his thinking mind, this does not prove that his body and his mind are distinct. The point is already made well by both Arnold and Gassendi, and quite a few of the objectors are incredulous at Descartes' views on non-human animals. In addition to all these concerns, the correspondents complain about omissions, in particular Descartes' failure to show that the soul is immortal.

But let's move on to less familiar fare, starting with the notorious Cartesian Circle. As Arnaud says, the problem here is that Descartes uses what he calls "clear and distinct ideas" to prove God's existence. Our conception of God is supposed to be such an idea, as is a premise Descartes uses in his first argument for God, that each effect can come only from a cause with as much perfection as it has.

How, though, do we know that we can rely on such obvious or clear and distinct ideas? Well, because we know that God exists. Being perfect, he is not a deceiver, like the evil demon invoked at the start of the meditations, so he would not create us in such a way that we are systematically misled by our clearest ideas. Hence the appearance of circular reasoning. We need clear and distinct ideas to prove God, but need God to prove that we can rely on those very ideas.

Descartes denies having made a mistake here, which is consistent with the tone of the replies in general. Not once, unless I missed it, does he concede any weakness in the arguments of the meditations. At most, he might admit that he could spell things out more fully or clearly, but usually he takes the objections to be misunderstandings, outright sophisms, or well-meant worries that can be easily dispelled.

He even declares his satisfaction that, if this is the best his critics can do, then the arguments of his meditations really must be impregnable. In the present instance, though, his response to the Circle seems to go beyond anything he originally said in the meditations. His reply seems to boil down to the idea that our clear and distinct ideas are reliable, even without God in the picture. Of course they are, this was never the issue.

Rather, the worry is that, having produced an argument on the basis of these ideas, one might then retrospectively wonder whether the argument was in fact as watertight as it seemed. In psychological terms, this is quite plausible. Imagine you do a fairly simple geometrical proof on Friday. While doing the proof, you can see that the ideas you've used are clear and distinct, and that the reasoning is impeccable. Then on Saturday, you mention to a friend that you came up with a proof for a theorem in geometry just yesterday.

Your friend says, and are you sure it was right? Since you are no longer doing the proof right now, you aren't having the same experience that the proof is obviously correct. You would have to run through the proof again now to relive that experience. Without doing that, the best you could say to your friend is, well, it seemed pretty certain yesterday. Descartes' response to the circle is along these lines. The proof of God is certain, so long as he's actively thinking about it.

But later on, when he's no longer actively thinking about it, he needs to know that God exists and would not be tricking him into believing that he's proven things when in fact he hasn't. And again, you can see why this makes sense. An evil demon could insert a false memory into my mind of having devised a rock-solid proof for some falsehood. But, once I've proven that God exists and is not a deceiver, I can rely on my previous use of clear and distinct ideas.

This would be why Descartes tells Mersenne that an atheist could not have certainty about mathematical truths, for instance that the angles of a triangle add up to 180 degrees. The problem for the atheist is not that he's unsure about this when he proves it, but an inability to be sure later on that he did in fact prove it. As Descartes puts it, the atheist cannot rule out that he is deceived even in matters which seem utterly evident to him.

Now, this is both surprising and rather unsatisfying. The whole point of the meditations, or so we thought, was to establish the reliability of certain principles for use in the rest of philosophy and science, especially physics. To achieve this, Descartes attempts to put everything in doubt. But he discovers a couple of things that cannot be doubted, no matter how he tries: his own existence and the existence of a perfect God.

On this basis, and especially given the existence of God, he can then assume that all the other things he takes to be principles are in fact principles. The whole procedure seems to presuppose that radical doubt does affect our apparently clear and distinct ideas, not just later on, but in the very moment we're having them. It seems like the evil demon hypothesis could undermine even our confidence in clear and distinct ideas about geometry, for instance, which for Descartes are a paradigm case of such ideas.

This is because geometrical truths are not like my own existence. I need to exist in order for the demon to trick me, but I don't need 2 + 3 = 5 in order for the demon to trick me. So such mathematical truths can coherently be doubted. As a result, contemporary interpreters have generally agreed that to break the circle, we need to say more than Descartes does in his replies. They don't generally agree what more should be said though. Among various alternatives, the one I find most persuasive is the following:

Even at the beginning of the meditations, when he is trying to doubt everything, Descartes says that even the senses tell us things about which doubt is quite impossible. For instance, that he is sitting by the fire wearing a dressing gown. Similarly, when it comes to basic geometrical facts, it seems impossible that such transparent truths should occur any suspicion of being false. Admittedly, it seems that when Descartes introduces the evil demon hypothesis, he finds that it is possible to doubt such things after all.

But is that really plausible? Surely, even in the depths of his radical skepticism, the meditator doesn't really doubt that he's sitting by a fire, or that 2 + 3 is 5. That would be insane. Rather, he's still psychologically convinced that these things are surely true. And of course, these things are really true, so he's also right to be convinced. What he lacks is a reason for trusting this feeling of inevitable certainty. This is the situation the atheist cannot escape.

When the atheist knows the angles of a triangle at up to 180 degrees, he rightly feels that this is something he just cannot doubt. His problem would come only when he reflects on such experiences. What if he's the sort of being who gets things wrong all the time, even when feeling very certain? Or what if he's subject to systematic trickery by an evil demon?

The way to banish these worries is by proving that God exists and is not a deceiver, using an argument that seems just as certain as a geometrical proof. Or in fact, even more certain, according to Descartes. With this reassurance, that we are not being deceived across the board, we can now rely on individual clear and distinct ideas. Descartes brings this out by referring to the intermittent feeling of certainty we get when actively thinking about things that are clear and distinct.

It's only afterwards, reflecting on the question whether we can rely on those feelings of certainty, that we realize we need to prove God exists in order to show that they are indeed reliable. Of course, even if Descartes can escape the charge of circular reasoning, his project will still collapse if his proofs of God's existence are not convincing. And here too, the objectors have their doubts. One question posed by numerous respondents is whether we really do have an idea of God,

After all, God is infinite, on Descartes' own account, and it doesn't seem that we can grasp infinity with our puny human minds. "True," answers Descartes, "but we can still understand what infinity means, the way we can see the entire ocean at once without grasping it in its depths." The objectors also challenge Descartes' claim that this idea needs to come from God himself. We could, it seems, just construct the idea from our experiences in everyday life.

We see that some humans have power and knowledge, and then imagine a being that has unlimited power and knowledge. Since this is an extremely plausible line of criticism, it's unfortunate that Descartes dismisses it in preemptory fashion. He says that forming an idea of infinity on the basis of finite experience would be like forming the idea of sound on the basis of having experienced color.

Another counter-proposal to Descartes was that we get the idea of God not from God himself, but from other people, like parents and teachers. And they don't have any more reality or perfection than we do. Descartes says that even if this were so, the idea must somehow have come to humans originally, and that the ultimate source of the idea must be as perfect as the idea itself, so it can only have been God.

But of course, Descartes does not really want to admit that we get the idea of God from our parents and teachers. Rather, it is innate, placed within our nature by God like a craftsman leaving a stamp to mark his handiwork. This talk of innate ideas prompts Gossendie to a particularly interesting line of attack on Descartes. He says that all the ideas mentioned by Descartes could instead be extracted from our experiences of the world around us.

Thus, the idea of triangle is not literally God-given, but something we come up with after having seen more or less triangular bodies. A pyramid, or if that's too expensive, a piece of pizza would presumably do the trick. Descartes' response is that we never encounter perfect triangles like those that we think about in geometry. This seems at first rather unconvincing, since it would presumably be easy to ignore the irregularities in a pyramid or the curve of the pizza's crust.

We are talking about clear and distinct ideas here. It is precisely Descartes' view that we arrive at such ideas by starting with ideas that are not clear and distinct, but rather confused. Then we use analysis to break down those ideas into their simplest, most well-distinguished components. So it isn't clear and distinct ideas that come from sense experience, but confused ideas that need to be refined. How could we do this if we didn't have the simple ideas within us from the start?

This skirmish in the debate with Gassendi goes by pretty quickly, but it's actually momentous, since it gives us a first taste of a defining debate of early modern philosophy as to whether human knowledge is based on inborn structures of reasoning or is entirely empirical in nature. Gassendi should also get credit for another powerful objection to Descartes' proofs for God's existence. As I mentioned, his second proof is a version of the medieval ontological argument.

Descartes updates the argument with his distinctive terminology, saying that the idea we have of God's nature entails that he exists. This is because we conceive of God as a being who has all perfections, and to an infinite degree. Since existence is one such perfection, it must belong to God. Therefore, God exists. Immanuel Kant is often credited with a fundamental objection to this argument, namely that existence is not in fact a perfection,

The idea of a really nice piece of pizza has exactly the same perfections as a real piece of pizza. It's piping hot, has a good dose of oregano, is succulent with cheese but not too greasy, and so on. The question of existence is totally different. It's just whether this item, with its various perfections, is realized in reality. This isn't making the piece of pizza better. It's more like flicking a metaphysical switch from off to on.

Now, it may seem plausible that Kant originated this objection, since it could have taken philosophers a while to free themselves from the pervasive ancient and medieval assumption that being comes in degrees and is a kind of perfection. In fact, though, the point is already made very clearly by Gauss-Sandy here in the objections. And in his own set of criticisms, Hobbes also wonders whether reality comes in degrees. Another clever response to Descartes' ontological argument is offered by Mersenne.

Before we can infer God's existence from the idea of God, we first need to make sure that idea is coherent. In other words, we have to show that God's existence is at least possible. Descartes is again fairly dismissive, retorting that the idea of God is simple, and so cannot involve any contradiction. But, Mersenne has put his finger on an interesting point. If God is possible, then he must exist, and so is necessary. But, perhaps he's impossible,

So, all we can establish with the ontological argument is that if God might exist, then he does. So far in this episode, I've focused on the first parts of the meditations, where the main themes are skepticism and God. But before wrapping up, I should mention that the objectors have plenty to say about Descartes' views on matter and mind as well. Gassendi, in particular, has some useful things to say here.

As we'll be seeing, he had his own sophisticated theory of matter, inspired by ancient atomism. So, he is unconvinced by Descartes' idea that matter is simply extension that can be indefinitely divided. Responding to Descartes' example of wax, whose sensible properties change while it remains extended in its nature, Gossendie says that we actually have no idea what would underlie the color, smell, and texture of the wax. After all, the only thing we have access to is these sensible features.

Descartes cannot just use his intuition to find out that the unknown subject underlying those features is divisible extension and expect us to agree with him. On the whole then, the objections and replies live up to the expectations we might have had when seeing the all-star lineup of opponents that Moussin managed to organize. A further confirmation, if one were needed, of his standing as a major node in the network that was the Republic of Letters.

Apart from Marcin himself, Hobbes and Gassendi were two major thinkers of the period, and Arnold was also a significant philosopher. Though Descartes saw the scholastics as his most formidable opponents, the two objectors who do the least to trouble him are the Jesuit Bourdin and the first objector, Johann de Cata, a priest whose citations of Aquinas show pretty well where he was coming from.

I find this quite significant. To an extent Descartes could not yet have appreciated, his real competitors were not going to be the scholastics. Rather, Cartesianism would have to contend with the other anti-scholastic philosophies that would emerge over the course of the 17th century. As the objections and replies begin to suggest, such rivals had already begun to appear, even as Descartes insisted that the arguments of the Meditations were the only sound basis on which to build a new science.

With that, we're pretty well done with the meditations, but not with Descartes. Mersenne and the other authors of the Objections were not the only outstanding intellectuals with whom he corresponded. There was also Elizabeth of Bohemia, who pushed him on aspects of his thought that we have not yet explored. His ethics, the nature of the emotions, and the connection between soul and body. These are our topics for the next few episodes, and I'd have no objection to you listening to them all, here on the History of Philosophy Gaps.

Thank you.