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Theory of Knowledge: Analyzing Knowledge #3 (Causal and Reliabilist Theories)

Video transcript

my name is Jennifer Nagel I teach philosophy at the University of Toronto and today I want to talk to you about analyzing knowledge this video looks at causal and reliable Asteria knowledge the causal theory of knowledge was proposed in 1967 by a philosopher named Alvin Goldman Goldman was convinced by Gettier but the justified true belief analysis of knowledge wouldn't work at least for the kinds of concrete facts that we know through experience of the world Goldman actually liked the JTB analysis for knowledge gained through pure reason in abstract fields like deductive geometry or arithmetic will set those fields aside in this video and focus on facts known through experience of the world such as the fact that Neil Armstrong was the first person to set foot on the moon or the fact that you are now watching a video goldman's causal theory of knowledge sets out to explain how we know facts of this kind and why the subjects of Gettier cases lack knowledge briefly the causal theory says that knowing a fact is a matter of having a belief that's caused by that very fact if you think about what happens in getting your cases where someone has a justified true belief without knowledge you'll notice that there can be a causal disconnect between the subjects belief and what is going on in the world consider the desert traveler who believes that there is water in the valley ahead because he's hallucinating even if there is water in the valley ahead that fact isn't playing a role in causing him to have this belief his belief is arising from some internal disorder he's suffering compare this to a case where you actually see water in normal perception the fact that the water is there plays a key part in the formation of your belief the water causes light rays to reflect into your eyes causing you to have visual experiences that cause you to form the belief that there is water in front of you Goldman's official formulation of his causal analysis of knowledge goes like this s knows that P if and only if the fact P is causally connected in an appropriate way with AZ is believing P appropriate causal connections include sensory perception testimony and inference for example you might know that Neil Armstrong walked on the moon even if you didn't personally perceive him doing it as long as there is the right causal chain between that fact and the formation of your belief if his walking on the moon caused certain televised broadcast to happen and those broadcasts cause others to know that Armstrong was walking on the moon and they wrote books which you read causing you to believe that Armstrong walked on the moon then your belief has an appropriate causal connection to the fact and it counts as knowledge Goldman's causal theory is interestingly different from the classical analysis of knowledge as justified true belief Goldman keeps the belief and truth conditions but as he adds his causal condition he drops the justification condition in Goldman's understanding of knowledge you don't need justification in order to count as knowing Goldman observes that for many random facts we count ourselves as knowing we can't remember how we came to know them right now you might not know who originally told you that Neil Armstrong walked on the moon or where you read or learned that he did if someone challenged you to state your evidence you might not be able to say very much but you still count as knowing the fact Goldman says as long as your belief was caused in the right way with a causal chain going back to the fact itself some philosophers have raised concerns about the idea of having knowledge without justification we'll explore those concerns in the upcoming video on internal ISM and external ISM other philosophers have worried about exactly what counts as an appropriate causal connection and they've crafted some puzzling cases where facts caused true beliefs through pretty strange routes cases where it's not clear what the causal theory should say but one of the main difficulties with Goldman's causal theory of knowledge is a problem discovered by Goldman himself a problem that led him to drop the original causal theory in favor of a more subtle theory known as reliabilism here's the story Goldman tells to illustrate the problem Henry is out for a drive in the country with his young son talking to him about the things they can see along the way look at the cow see those horses Hey look over there it's a barn and indeed Henry is looking at a barn when he makes that last remark we'd ordinarily say that Henry knows that what he sees as a barn but there's a twist in the story Henry doesn't know this but he's driving through fake barn County where for some reason the locals have decided to put up a lot of barn facades structures that look like barns when you see them from the highway but a really just Hall of fronts and not barns at all as he's been driving and looking at things by the road 99% of the things that have looked like barns to Henry haven't been barns at all and he's just lucky that the one he's passing right now actually is a real barn with all of those fakes around Goldman suggests it doesn't seem that Henry really knows that what he's looking at is a barn notice that there's nothing wrong with the causal chain that is generating Henry's belief that there's a barn in front of him now there is a real barn causing Henry to believe what he does in the normal perceptual way according to Goldman the problem here is that Henry is forming his belief in a way that is unreliable given his current environment even if you can ordinarily tell that something is a barn by glancing at it from a distance in fake barn County this way of judging is likely to generate a false belief the core idea of reliabilism is that someone has knowledge if and only if they have a true belief formed by a reliable belief forming process there are many different ways of fleshing out that core idea but it's broadly agreed among reliable ist's that a belief forming process doesn't need to be perfect in order to generate knowledge you can gain knowledge through your visual system even if that system could be fooled by a purely hypothetical mad scientist as long as that system is likely to deliver the truth in your actual environment you can gain knowledge through it there are several well-known objections to reliabilism one of them is the generality problem anytime you form a belief you are using some belief forming mechanism and we have to identify it in order to classify your belief as reliable or not but it can be tricky to isolate the right mechanism note in particular that it can make a difference whether we pick out a really general or really specific mechanism if we say that the relevant mechanism in Henry's case is his visual barn detecting capacity as exercised in fake barn County then that mechanism is indeed unreliable fitting the intuition that Henry lacks knowledge but if we zoom out and identify the mechanism as sensory perception that remains pretty reliable even in the county Henry doesn't lose all sensory knowledge as he drives through on the other hand if we zoom way in and identify Henry's belief forming mechanism adds visual barn recognition directed at this very barn at the instant he's looking at the real barn once again we have a reliable mechanism a hundred percent reliable in fact it's not trivial to figure out how to identify the relevant mechanism when we're deciding whether someone has knowledge and it remains controversial whether rely on lists have a natural way to do this that's the generality problem another objection raised against reliabilism is the lottery problem imagine that you have a ticket in a fair lottery with a million tickets sold the draw has just been held but the winner hasn't been announced can you know already that your ticket has lost if pessimistic Pierre believes that his ticket is a loser just on the strength of the long odds against it he is 99.9999% likely to be right that's pretty high reliability but it may seem to you that even if Pierre has lost he can't know that he's lost until he hears the winning number announced this could be a problem for at least some forms of reliabilism lastly the intuitions motivating reliabilism are somewhat controversial Alvin Goldman had the sense that Henry didn't know he was looking at a barn but not everyone feels that way about the story if you feel that Henry does actually have knowledge here you're not alone some prominent philosophers like Ruth Milliken are on your side it's not clear why people feel differently about these cases we may have different ways of imagining how Henry's thinking as he's driving along perhaps we're imagining him as using more or less general belief forming mechanisms perhaps Milliken imagines Henry as very focused on this one barn and reliable where Goldman sees him as engaged in an ongoing inquiry about all the roadside attractions in this county and unreliable about barns it may help to think about the scenario in different ways or think of other scenarios you might find new problems for reliabilism or new ways of defending or refining it the next video in this series looks at tracking theories of knowledge which are close cousins of reliable as theories