PHILOSOPHY - Epistemology: New Responses to Skepticism [HD]

How do contemporary philosophers respond to the threat of skepticism? In this Wireless Philosophy video, Jennifer Nagel (University of Toronto) reviews the semantic (or meaning-based) theories of Hilary Putnam and David Chalmers, according to which skepticism either self-destructs, or isn’t as scary as you might think. She then examines the defensive approach of Timothy Williamson, an approach whose goal is not to convert you from being a skeptic back into believing in knowledge, but rather to protect you from becoming a skeptic in the first place.

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[laflaca]

I liked Chalmer's argument, it seems to me the most humble (not sure if this is the right english word)

[LimeyLassen]

That immune system analogy is surprisingly satisfying.

[Roadcastermusic]

Interesting that Chalmers view resembles the view of Buddhist philosopher Nagarjuna who is said to have live around 150-250 CE. Nagarjuna divided philosophy in practical and ultimate truth. Most of what we experience and that concerns our sciences is at a practical level. The practical level gives us knowledge of the world that is of practical use to us, in a wide sense, but it isn't ultimate truth. What is ultimate is not totally agreed on within buddhism (from what I understand) but an often appearing candidate is 'change' - what ultimate is true is that everything is in a constant state of change. Anyway, really enjoyed the video:)

[leviangel]

I am largely in support of the second method. I am also really enjoying this channel so far.

[smilyle]

The "How" of how of how I know something is true is under no obligation to be explainable to anyone, not even myself. I don't have to know how I know - to know that I know. Because all I have to do is find something that doesn't know how it knows, and we don't know how it knows, but we know that it knows, and the suppressed premise of the Skeptic that 1) you can't say you know something is true without being able to make understandable to everyone how it is true and 2) that something can't be true unless everyone can understand an explanation as to how it is true, is utterly refuted. There are some truths that not everyone can understand. And the mere observation that someone doesn't or can't understand or explain how they know something, and just because you don't know how they know something, is not a valid argument as to why they, in fact, don't know what they are saying is true. Philosophical Skepticism is a form of the infinite regression fallacy.

[SpionCTFT]

Why is scepticism presented as a threat - As an opponent? As if it was not a legitemate point? Is it maybe just a bit biased?

[jakeb.]

Very partial approach to skepticism. No skeptics would describe themselves as having those goals or beliefs.

[thomas.leitner]

Wow, that must be a bad constructed simulation, if the simulation questions itself...

[wwart_]

This was an extremely helpful video. My thinking has very strong skeptical tendencies, to the point where it actually is difficult for me to live day-to-day life sometimes because I'm always doubting everything. I've been trying to sort out my beliefs about morality, ethics, and God. But when even basic practical knowledge seems open to question, what hope is there of coming to terms with those higher-order concepts? On what basis could one even begin to make an argument? People I've spoken to about it have appealed to common sense (like the first and third arguments Professor Nagel presented), but so far I have not found such arguments convincing because they simply assume arbitrarily what must be proved: that human senses, cognition, and/or intuition provide accurate information about reality. It seems to me that we have no reliable way of assessing the accuracy of our own perceptions. It's quite possible (maybe even probable) that some of what we refer to as "common sense" is in fact a collective delusion of our species.

It seems to me that David Chalmers's approach finally offers some hope, however. I may not be able to "know" whether or not I have hands, but I can know at least that I perceive myself to have hands. And it seems fairly reasonable to assert that such perceptions offer at least SOME true information about reality, provided we acknowledge that this information is very likely to be flawed or incomplete. For instance, if am hallucinating and perceive that I have hooves instead of hands on my arms, that perception corresponds to something real: in this case some kind of process going on in my brain that causes me to hallucinate. (This position still would seem to require the assumption that if I perceive something, then there must be some cause for that perception--but perhaps that is a rookie mistake on my part. I know that causality has been another hot topic among philosophers and one that I haven't been able to investigate much so far.)

The most likely scenario would seem to be that there is an objective reality of some sort; that human beings have the capacity to acquire some knowledge of that reality through our sensory and cognitive abilities; but that the sum total of all possible human knowledge may well correspond only to a very tiny percentage of what a superhuman being could know about reality.

[AntiCitizenX]

Words mean things. Therefore, I'm not a brain in a vat...

huh?

[vhawkkl]

Why d-e-f-e-n-d against scepticism?-What is threatened by it?-Religion?

What would be a clear example of "Knowledge"- or bench mark or comparator for establishing knowledge?- as " known" as what?

[samuelwoods]

my dad's name is Brian, therefore my dad is a brain in a vat. This philosophy is way ahead of its time.

[momodycath]

Chalmer's argument seems the most reasonable one, to me. He doesn't try to attack skepticism as if it was a bad thing, a problem to be solved. If anything, his argument is an acceptance of skepticism, while at the same time arguing that even if reality was "simulated" or "dreamed" or "non-physical", it would still be perfectly describable as real and valid.

For example, imagine that a highly advanced society made a VR video-game in which you can truly feel sensations such as pain or pleasure. If someone were to stab you, it would be entirely valid to feel angry at that person. It would not be valid for that person to say that "Since this sword is virtual, your pain is false". In that way, it doesn't matter that the sword is virtual, it is still a "real" sword, and it still has real consequences. Just like a perfectly simulated universe would be "real", even if it was simulated.

Of course, this doesn't solve the problem of the existence of consciousness and the moral questions that it entails, but as far as validating knowledge and perception, it's a good argument that I particularly agree with.

[KMEthridge]

tl;dw:
1. You cannot be in a computer simulation because you don't have the words to describe outside of the simulation. It's not like a simulated world would be based on the outside world.
2. Even if you are in a simulation, your experiences are real to you.
3. What is even knowledge?

[khaledyasser]

The "defensive approach" is literally ad-hominem. "It's just a phase dude, ur wrong"

[Medeasbiggestfan]

Hilary Putnam died of cancer on 13 March 2016.

[DarrenMcStravick]

Here's a way to combat skepticism combining both Moore's and Putnam's responses:

*(AP) A subject can know, a priori, the contents of their thoughts.*
- This is typically justified via an account a priori knowledge that your chosen theory of mental content satisfies.

*(CE) Thought content is partly determined by environmental conditions.*
- This is typically justified via a specific theory of mental content and/or through intuition pumps for content externalism (see Putnam's Twin Earth and Burge's Arthritis thought experiments).

*(Definition) Let 'E' be the condition that (CE) requires for a concept to have external, and not simulated, hand content.*

*(Premise 1) If subject S is thinking that "here is one hand (and here is another)", then E obtains.*
- Can be known a priori if (CE) is true, given that one's theory of content is entirely a priori.

*(Premise 2) Subject S is thinking that "here is one hand (and here is another)".*
- Can be known a priori if (AP) is true, which again, rests on the a-priority of what you take mental content to be.

*(Conclusion 1) Therefore, E obtains.*
- i.e., there is external hand content.

*(Premise 3) If S is a brain in a vat, then it is not the case that S's thinking that "here is one hand (and here is another)" is true only if there actually exists both hands (i.e., that E obtains).*

*(Premise 4) But S's thinking that "here is one hand (and here is another)" IS true only if there actually exists both hands (i.e., that E obtains).*

*(Conclusion 2) Therefore, S is not a brain in a vat.*

[pafnutiytheartist]

I have a pretty stong argument against semantic externalism. We precieve vats brains and anything else through our sences. If a computer progtamm can reasonably accuratly recreate the impulses from our sensors to the brain what is the difference between simualtion and rality for an individual? In both cases you don't name actual objects but rather sensations that objects create in your brain. The sensations are pretty much the same, so why would a brain in a var have different concepts than a real person?

[unlesssly]

The way I use skepticism in everyday life is to look at things through the lense of "the best available evidence at this time points to X" and make decisions based on that, while acknowledging that the conclusion could still be wrong and that the evidence could evolve or be disproven later on. It doesn't lead to rational paralysis where I can't form opinions or beliefs about anything. I have been challenged by those who would say I should question even my ability to identify the best available evidence, and certainly, this is a problem worth examining especially in the age of disinformation and fake news. So how do we solve this problem and find a way to validate our ability to evaluate evidence? Possibly, we could set up test scenarios where a group of people set up a puzzle or mystery rooted in objective (or at least, intersubjective) reality and then bring in a third party participant to try and solve it. A pattern of success in these types of trials (especially in the face of red herrings and misinformation sprinkled in with the real evidence) would probably be the closest we could get to verifying our own rational abilities.

That aside, I didn't really understand the first argument as it seemed to imply we couldn't possibly be in a simulation that provided information similar to reality outside the simulation (i.e. brains and vats); or did I misunderstand the argument?

I don't really see how the second argument is an argument against the epistemological validity of skepticism so much as an axiological argument about the value of skepticism (whether our reality is made of matter or code, why does it matter/what's the point of asking?). Well to me, asking questions about the basic nature of reality is important because many logical assumptions depend on that. If we're inquisitive about whether reality is made of code written by a programmer, we could possibly anticipate and prevent scenarios where that code is drastically altered or deleted without our consent. We have no way of determining that at this time, but in the future who knows? If no one asked the question then nobody would look into it at all. We have the knowledge we have about our universe today BECAUSE people dared to ask questions about the nature of reality, and we have a better understanding of it now as a result of observation and data collection. On the other hand, if we just assume the world is controlled by supernatural deities we can never fully comprehend or unpredictably chaotic forces of nature, we will continue to sit on our hands and may learn nothing. Skepticism leads to investigation and learning because it causes us to consider all possibilities rather than a limited set of alternatives.

[TheRMUPs]

Some of these responses, old and new, aren't even real arguments. They're just people telling you to "build up your defenses" or "become stubborn and deny the pull of skepticism". And the ones that ARE arguments against skepticism all fall apart very easily. Why are people trying so desperately to stay away from skepticism, when it is obvious they can't find a single reason for it being false? Why are they attributing manipulative descriptions to "the skeptic", as if they were vile creatures attempting to doom us all. Some people think skepticism is just an excuse not to care about science, but that just isn't true, because even if everything is false, knowing that everything is false won't snap us out of the illusion. We're still always subject to it, so we would still live our normal lives, with our normal curiosity, with the knowledge of a possibility in the backs of our minds. So I just don't get the aversion people have to skepticism. Why are people so desperate that they would publish such weak arguments, just to get away from something so benign. Philosophy is the search for knowledge, the love of wisdom, so to deny a possibility because it is convenient for you to do so is the worst affront to the field, and betrayal of yourself you could possibly commit. Stop holding back knowledge by making us stagnate on this one point and just accept that you see nothing fundamentally flawed with the theory.