Lately I’ve been reading Outline of Pyrrhonism by Sextus Empiricus. Sextus collects the arguments for Skepticism as practiced by ancient Greek and Roman philosophers. Since the notion of “skepticism” seems to play some small role here, I thought it would be fun to take a look at what Sextus means by it.
Sextus situates skepticism as the only reasonable response to “dogmatism”. The dogmatists he has in mind are Platonism, Stoicism, Epicureanism, and Aristotelianism (“the Peripatetics”).
He observes, firstly, that the dogmatists all contradict one another — if Stoicism is right, then Epicureanism must be false; if Epicureanism is right, then Aristotelianism must be wrong, etc. What are we to do when dogmatism contradicts dogmatism?
Sextus then observes that none of these positions is “self-evident”, because all of them requires “going beyond the appearances” by making claims about what is “nonevident”. In order to do make claims about what is nonevident, the dogmatist must always either make a circular argument that assumes what they purport to establish or commit themselves to an infinite regress. On this basis he concludes that it is not reasonable to make claims about reality one way or the other. Instead the Skeptic endeavors to live only according to the appearances, and be guided only by what is immediately evident to the senses.
A nice corollary of Sextus’s arguments is that one cannot be a naturalist and a skeptic, since the naturalist does make positive claims about the nature of reality. Naturalism and theism effectively cancel each other out.
The dialectic between dogmatism and skepticism stretches out across the whole history of philosophy. The re-discovery of Stoicism and Epicureanism during the Renaissance re-activated the ancient quarrels between competing dogmatisms (though with a different political dimension, since by this time Aristotelianism had become, thanks to Aquinas and subsequent theologians, the official doctrine of the Catholic Church, which its entrenched power structure). So the quarrel between competing dogmatisms had a political dimension that it seemed to have lacked in antiquity. The revival of Skepticism, most notably (to my mind) with Montaigne, then leads to renewed efforts to establish dogmatism by refuting Skepticism. (This did not prevent some philosophers from attempting to integrate Christianity and skepticism, as Pierre Gassendi did.)
Descartes was, as we know, the most famous (or infamous) of attempts to refute skepticism. But as was pointed out even then, Descartes’ arguments do not avoid circularity. (I believe it was Antonin Artaud who first made this point in first, in his Objections to the Meditations. Descartes’ Reply is, to put it mildly, not convincing.)
The inconsistencies within Cartesian dogmatism led to multiple and contradicting attempts to repair it: Spinoza, Leibniz, Malebranche, and Berkeley being the attempts that have since made it into the Canon (largely because they were all men). At the same time, Pierre Bayle is collecting the new Skepticism into what amounted to a new version of Outlines of Pyrrhonism for the modern era. Following on the heels of all of them, it fell to Hume in his Treatise on Human Nature to demolish all permutations of modern dogmatism by destroying their basis in Cartesianism.
Since then, the dialectic runs back and forth between competing dogmatisms and between dogmatism and skepticism. Kant was perhaps the first philosopher to even attempt a genuine via media between dogmatism and skepticism, but the fatal problems with Kant’s solution are well-known to most casual students of philosophy.
To this day it remains unclear whether there is a via media between dogmatism and skepticism. Some philosophers, including myself, think that the historical arc of pragmatism that runs from Hegel through Peirce and Dewey to Sellars should be understood as precisely an alternative to both dogmatism and skepticism. Others, of course, are not convinced. And so we have the persistence of both multiple forms of dogmatism — naturalism and theism alike — as well as new forms of skepticism.
Can a naturalist be a skeptic? Is skepticism more reasonable than any competing dogmatism? Is skepticism a viable philosophy as a way of life? Is pragmatism a dialectically stable alternative to dogmatism and to skepticism, or must it collapse into one or the other?
I should spend more time going back through previous comments, lol.
Well, keiths, should we follow your example and become Cartesian Skeptics, since the skeptical hypothesis hasn’t been disproven? The answer would appear to be yes. Let’s all adopt the attitude that if you cannot disprove my beliefs then they are reasonable.
All in favor?
That seems logical, and rational. Is it ok for anyone else who applies that same logic? Because I get the sense from other comments that you’ve made that other people don’t get a pass for doing the same thing you’re doing.
Poor Mung. Just as baffled as fifth was by the notion of a probabilistic argument.
Hint: Fifth was talking about logical disproof, against the idea of a probabilistic argument.
So you’re probably a Cartesian Skeptic but there’s a chance you may not be?
keiths,
I’d have guano’d this had I seen it sooner. Please make complaints about individual moderation actions in the appropriate thread.
Exactly. Dennett talks about “folk physics” being generally reliable in contrast to “folk psychology”. Here
Of course I agree with Reciprocating Bill that evolutionary theory can explain why the senses are reliable, to the extent that they are — and also why they aren’t, to the extent that they aren’t.
But the Skeptic will want us to establish that the senses are reliable prior to our doing any science at all, including evolutionary theory. Otherwise our naive confidence in the reliability of our senses would be just a dogmatic assumption to which we are not rationally entitled.
And of course one cannot establish the reliability of the sense by appealing to the senses. Likewise one cannot establish the reliability of the intellect by appealing to the intellect, etc.
Alan,
No doubt you would have.
KN,
Or to keep in mind that it hasn’t (and can’t) be established as we nevertheless proceed to do science.
It’s good to see you emphasizing this now. In our earlier discussions, you were were trying to evade this by watering down your standards of justification, which led to all the trouble you had with the Sentinel Islander thought experiment.
I originally intended a longer answer, but decided it would be better to start with a short answer.
Harnad described the intentionality problem as “symbol grounding.” But you won’t find scientists doing much symbol grounding. They do it the other way around. I sometimes describe that as “symbolizing the ground.”
Philosophers (i.e. most people, not just professional philosophers) seem to want to start with concepts, and then wonder how they connect to reality. But science starts with what it can connect to in reality, and then creates concepts out of that. So the most important scientific concepts are grounded from the get go. This is really what operational definitions are all about.
Science starts with ideas such as measurement. People seem to take measurement as just something that we do. But a lot of work goes into inventing ways of measuring. That’s the sort of low level activity that I was referring to. And when a way of measuring is invented, it is usually done in a very systematic method. The “unreasonable effectiveness of mathematics” is really the mathematics of the systematicity of that invented system of measuring, so it is not actually unreasonable. But people are looking for a high level explanation of why mathematics is useful, instead of looking at the low level systematic methods.
Science builds its concepts on top of what it can already measure. That’s why its symbols are grounded. In ordinary life, the connection between our concepts and reality is far more haphazard.
I should add that string theory and multi-verse theory (in physics) are not done as I described. So the symbols from those theories are not well grounded. That’s why those theories come into a lot of criticism.
KN, Sextus then observes that none of these positions is “self-evident”, because all of them requires “going beyond the appearances” by making claims about what is “nonevident”.
Is Sextus assuming that only appearances are self-evident? Isn’t it experientially evident enough that appearances are deceptive and in order to know the truth/reality one absolutely must go beyond appearances?
If “reliability of the senses” just means that we can rely on them, then in fact we do rely on them and seem to survive. So it seems to me that we can establish the reliability of the senses in that pragmatic sense.
If, however, “reliability of the senses” is supposed to mean that they deliver truth — I am unable to actually make sense of that. It seems a serious mistake to expect “reliability of the senses” with that meaning.
As far as I can tell, Sextus would say that we can notice similarities and differences between appearances — what appears to be X at t1 will appear to be Y at 12, will appears to be Z at t3, and so on. But he would probably have to say that we would already be in the grip of Dogmatism in order to say that appearances are ‘deceptive’ just by virtue of undergoing constant change.
And notice: Sextus is arguing against the idea that we can know truth/reality! That’s the very heart of the Skeptical challenge to all dogmatic metaphysics, of whatever variety!
That makes sense. As has already been said, our sensory/motor system has been honed by evolutionary feedback to work well enough to get by in our niche.
Now that (“just by virtue of undergoing constant change”) was not what I said, Sextus, was it? Rather, I would point to the self-evident that you like so much: mirages, optical illusions, distortion and loss of sense-perception when tired or asleep, etc.
Anyway, you seem to be agreeing with unreliability of the senses, so let me simply point out that by throwing out “dogmatism” as you call it, you will have nothing to stand on whatsoever. This baby goes together with the bathwater.
Well, then he is ultimately not arguing at all, because he is evidently not arguing for anything 🙂
In a sense, yes. He’s arguing against all metaphysics (as he understood it).
I started getting interested in ancient Greek skepticism due to my interest in Hegel and to some extent in Peirce. I want to understand pragmatism at a deep level as a philosophically adequate treatment of skepticism, because of how the process of reasoning, as historical (taking place in time and as accumulating a background over time) and as social (as an activity that takes place in the mutual give-and-take between differently embodied-and-embedded cognitive agents).
The Dilemma of the Criterion trades on the fact that any criterion of evaluation can be made itself an object of evaluation — we can always inquire whether our epistemic norms should be revised in some way or other. But I want to push back against the thought that our justifications need to be themselves justified in order to function as justifications in the first place.
Whatever reasons we present for our judgments are always situated within the activity of reasoning. Reasoning as activity, as something that we do, should in turn be understood as a norm-governed social practice. But we could not play this game of giving and asking for reasons if it were not the case that we are, in fact, embodied beings that are cognitively sensitive to some minimal threshold of observable regularities and irregularities. Without this fundamental background, the very process of reasoning would make no sense.
And that means that there are some ‘foundational’ ontological commitments that are immune to the Skeptical challenge.
Neil:
That’s why I tend to use the word ‘veridical’ instead of ‘reliable’ in these discussions.
It’s not a difficult concept. A perception is veridical or non-veridical in the same way that an empirical proposition is true or false — it either corresponds to reality or it doesn’t.
I perceive myself as a physical being, situated in space in front of a computer monitor, with a gray tabby cradled in my left arm as I type one-handed on a keyboard. To the extent that those things are actually true, my perception is veridical. If I am really a brain in a vat being fed “sensory” data intended to create the illusion of the body, the monitor, the tabby, and the keyboard, then my perception is non-veridical.
Alan,
That misses the skeptical point entirely, which is that all the information each of us has about our sensorimotor system and its evolutionary provenance comes to us through that same sensorimotor system. To use it to argue fror the veridicality of the senses is therefore hopelessly circular, like trying to pull yourself up by your bootstraps.
I’m a pragmatist. I’m satisfied that the information that comes in via my sensory system is generally reliable, though I can be fooled! When I find that there is some point to worrying about whether I might be a brain-in-a-vat, then… I’ll carry on. And I don’t argue that the senses are veridical*. It’s not black and white. Sensory information and processing and how the organism profits from it is a continuum. Plants manage to live without the benefit of any sensory information.
*”Veridical” applies to speech not senses.
Alan,
You already established, the last time around, your lack of intellectual curiosity on this subject. That’s fine, but don’t be surprised when others who are curious discuss skepticism in a thread dedicated to the topic.
Obviously. Hence my statement:
Alan:
No. We’ve been over this already, but the lesson was evidently lost on you.
If you can’t gin up an interest in skepticism, could you at least summon a curiosity about what’s between the dictionary covers?
Which subject? I’m dismissing pretentious thought experiments of the zombie, brain-in-a-vat and sentinel islander genre as a way of making any discovery regarding reality. I’m skeptical of such nonsense.
Etymology is from verum (truth) and dicere (to speak).
ETA looking back at that thread you link to, I don’t see any reason to shift my view that veridical is inappropriate when talking about the quality of sensory perception.
Alan:
I addressed that already in the linked comment. Another lesson lost on you.
keiths,
Referred to it. I remain unimpressed. Call the grammar police!
There’s actually a serious point here. If you intend to communicate an idea and the words you use are open to interpretation, it’s worth trying a paraphrase or two.
As applied to the senses, “veridical” doesn’t actually mean anything. Well, I suppose it could mean something if you are a theist. But, otherwise, it doesn’t mean anything.
That doesn’t mean anything either.
In order for that to be meaningful, you would need to first have a separate definition of “corresponds to reality”. And that separate definition must not use “true”. It cannot be done.
Unless you are a theist, the correspondence theory of truth really boils down to: An empirical proposition is true if it is true. And that doesn’t say anything useful.
Alan:
Says the guy who just scolded me for supposedly misusing the word, and now has egg on his face.
You can be so clueless sometimes, Alan.
keiths:
Alan:
Skepticism, obviously.
To your detriment. For example, the thought experiment I introduced in the other thread would have helped you avoid the mistake you made there. Thought experiments are extremely useful to those who understand how to formulate and deploy them.
How do you figure that? You really shouldn’t be such a drama queen. I think you misuse the word. Nothing you have said so far persuades me otherwise. Whence the egg?
That’s an evidence-free claim that you could try and support.
Alan:
Oh, the irony.
keiths,
It depends on your point of view, I guess. I’m not sure if it’s off-topic but I’d still like to hear about how philosophical zombies, brains-in-vats or fooling sentinel islanders in thought experiments advances cognitive science.
keiths:
Alan:
I did, in the sentence just before the one you quoted:
keiths,
No, that’s an evidence-free claim, too. Seriously, try and support the idea that your sentinel islander nonsense leads to useful conclusions.
Alan,
The thought experiment highlighted your mistake. Are you saying that you would have persisted in the error after having it highlighted so prominently?
Actually, that’s quite plausible, given your childish denial above of your mistake regarding the usage of the word ‘veridical’.
A one-sentence summary might be something like this:
The Sentinel Islander thought experiment shows, by analogy, why it is illegitimate to assume the veridicality of perception in an attempt to avoid Cartesian skepticism.
If you want more detail, go back and read the threads.
You have an unfortunate tendency to dismiss things not because you find actual flaws in them but merely because you don’t understand them. That’s a serious mistake, and it’s especially unfortunate with respect to your inability to understand thought experiments.
“Read the threads” is hardly providing evidence. I’m asking if you can provide evidence that your thought experiment led to useful conclusions. I’m off to bed now so there’s no rush. Of course there’s no obligation.
Alan:
Of course. The threads themselves provide the evidence. Are you willing to do some work by actually reading through them, or will you simply continue to dismiss what you don’t understand?
Here’s a good place to start:
See if you can at least understand the simple thought experiment itself. I remember that you had some trouble with that on one of the other threads.
Neil:
Like Alan, you’re repeating a mistake that has already been pointed out to you:
There might be some thought-experiments that help advance cognitive science, but surely not those.
The question I’m interested in (and I might be the only one here interested in it, which is fine) is how to think about pragmatism as an intellectually respectable response to skepticism, rather than as a mere shrugging of the shoulders.
Pragmatism is said to have begun with Peirce’s maxim, “let us not doubt in philosophy what we do not doubt in our heart”. There is, he thought, a difference between genuine doubt and artificial doubt. Genuine doubts happen rarely in everyday life and often in science (which is worth reflecting on in itself), when we find ourselves perplexed or confused or not knowing how to proceed. But the lack of familiarity shows up for us against a background of tacit knowledge, background beliefs, and what can be taken for granted in that specific context. By contrast, artificial doubt attempts to put everything in question, all at once; it undercuts the whole movement of thought so that it can’t move in any direction at all.
I take it that Alan is basically saying that artificial doubt can’t help us answer questions that matter to us. If that’s what he’s saying, then I quite agree.
I disagree with the thought that the correspondence theory of truth stands or falls with theism. But I do think that, even if the correspondence theory of truth can be put in a non-theistic framework, then however sentences correspond to reality — <if they do — sensorimotor abilities don’t. That’s why I don’t think it makes any sense to think of perception as “veridical”.
No, I am not making that mistake.
You are making a serious mistake by taking that to be what I am saying.
Here’s an illustration of the problem with the idea of veridical perception.
For all you know, when I am looking at a dog, my perceptual experience might be the same as the perceptual experience that you have when you are looking at a banana.
I learned all of the dog words based on my “banana” experience. So you cannot tell from my language that my experience isn’t the same as your dog experience. And if I were to draw a picture of a dog, I would draw it so that it looked right to me. That is to say, I would draw it so that I had the right kind of “banana” experience. And that means that my drawing of a dog would look like a dog to you, because the things that look like dogs to you are what produce my “banana” experience.
*** and a footnote: my spell checker (with “vivaldi” browser) does not like “veridical”. It thinks it should be “vertical”.
We can agree to disagree about that.
I usually don’t criticize your view of truth, because you don’t try to push it as far as keiths does.
Neil:
It’s there in your own words, Neil:
As I said:
There doesn’t have to be a bird to take a birds-eye view of a building, and there doesn’t have to be a God to take what you’re calling a ‘God’s eye view’ of the truth.
You made a simple mistake, Neil.
KN,
That strikes me as odd. Let’s take walto’s favorite example of the cow that is, or isn’t, in front of him.
I would say that the sentence “There is a cow in front of me” is true if there is in fact a cow in front of me, and false if there is not.
I would likewise say that the perception of a cow in front of me is veridical if there is in fact a cow in front of me, and non-veridical if there is not.
What’s the difference? Why do you balk at referring to perception as veridical or non-veridical if you don’t balk at referring to sentences as true or false?
Alan:
KN:
Alan’s queston is tendentious. The pertinent question is whether thought experiments can serve their intended purposes, not whether they achieve whatever goal Alan assigns to them. And the answer, obviously, is yes.
Alan isn’t particularly well-read, so he may not realize how ubiquitous thought experiments are, in both implicit and explicit forms. They are used by philosophers, scientists, economists, and thinkers of many other stripes.
KN,
Untrue. My Cartesian skepticism doesn’t stymie my thought at all. I’m just aware that when I reason on the basis of sensory data, my conclusions are dependent on the veridicality of that data, which cannot be guaranteed.
It’s simply being honest about the human condition, and it doesn’t impair thought in the slightest.
KN,
Why do you think that there even needs to be a response to Cartesian skepticism, apart from simply accepting it? As you acknowledge, you cannot refute it. Why not accept what you cannot refute?
Your response to a request for evidence of usefulness is to link back to your original proposition ? Very useful. 😉 Assume, against the evidence of your impeccable mind reading abilities, that I at least have the understanding of a six-year-old child. I’d remind you of Einstein’s remark: “If you can’t explain it to a six year old, you don’t understand it yourself.”
Interesting–and very Quinian–post, Neil!
Firstly, what I think cannot be “refuted” is Pyrrhonian skepticism, which is what I’m reading about in Sextus. That’s a different and in some respects more profound view that what you’re calling “Cartesian skepticism”.
Secondly, the view that you’re calling “Cartesian skepticism” relies on some problematic assumptions:
The function of the senses is to furnish the mind with sense-data.
The truth-value of a sentence can be determined by whether or not the sentence corresponds to a state of affairs.
Perceptual states are collections of sense-data.
Perceptual states are veridical or non-veridical in the same way that sentences are veridical or non-veridical.
It seems to me that you are committed, or would need to be committed, all of these claims in order to generate your argument for “Cartesian skepticism”.
And I think that all of those claims are false.
As Hegel points out (in the Introduction to Phenomenology of Spirit), what seems to be skepticism about the external world is actually dogmatism about cognition.
(I’m putting “Cartesian skepticism” in scare-quotes because keiths view is much more like Hume’s, though without Hume’s admission that skepticism about the veridicality of the senses applies just as much to the intellect.)