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Theory of Knowledge: Analyzing Knowledge #1 (The Gettier Problem)

Is knowledge the same as justified true belief? In this Wireless Philosophy video, Jennifer Nagel (University of Toronto) discusses a Gettier case, a scenario in which someone has justified true belief but not knowledge. We’ll look at a Gettier case from Edmund Gettier’s famous 1963 paper on this topic, and a structurally similar case from 8th century Classical Indian philosophy.

Speaker: Dr. Jennifer Nagel, Associate Professor, University of Toronto.

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  • blobby green style avatar for user Sam

    Previous videos had it at the bottom but now all you guys have is the time stamped transcript which you can't even copy and paste. Ugh!
    (4 votes)
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  • starky ultimate style avatar for user Averatu
    How can looking at a clock be a justification of a belief when it is the source of the belief to begin with! To justify this belief you would check the time on your phone. To use the source of a belief as the justification is begging the question.
    (2 votes)
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  • orange juice squid orange style avatar for user Jenny
    Hmm..so how does this justified confident belief work with the Dunning-Kreuger (sp) effect?

    As knowledge rises, confidence in knowledge falls and vice versa.
    (1 vote)
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  • orange juice squid orange style avatar for user Krzysztof Brejnak
    What's the point in discussing knowledge along the lines of JTB+X while we can never tell if something is a justified true belief or a justified false belief anyway?
    (1 vote)
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Video transcript

my name is Jennifer Nagel I teach philosophy at the University of Toronto and today I want to talk to you about the Gettier problem this problem gets its name from the philosopher Edmund Gettier who published a very short and famous paper on it in 1963 in his paper Gettier sets out to attack the dominant theories of knowledge of his day which were committed to a three-part analysis or definition of knowledge according to this analysis a person or subject who's conventionally called s knows a proposition let's call it P if and only if the following three conditions all hold P is true s believes that P and s is justified in believing that P this three-part recipe is known as the JTB or justified true belief analysis of knowledge the first two conditions are pretty uncontroversial knowledge only latches on to truths and you need full confidence or belief to know if you just have a hunch that's not enough we need the third condition because knowledge demands more than true belief you may remember pessimistic Pierre from our first video in this series who wakes up in a windowless room every day believing that it is raining outside even on a day when this pessimistic belief is true it doesn't seem right to say that he knows that it is raining he lacks justification the nature of justification is controversial different JTB theorists had different ideas about it but let's say it has something to do with having good reasons for your belief if we don't want the JTB analysis to be a circular definition we have to say that being justified isn't the same thing as knowing get eager suggests one possible difference he observes that you could in some sense be justified in believing something that turns out to be false for example if you had lots of misleading evidence that made it look like the right thing to believe if you're justified belief turns out to be through then the jTBC theorist has to say that you have knowledge you might wonder whether that's right or more generally what needs to be added to true belief to get knowledge that's the Gettier problem Gettier himself didn't think the JTB analysis was correct and he came up with some counter examples to it where someone has a true and justified belief but seems not to know here's his first counter example Smith and Jones are rival job applicants getting or doesn't say how but they meet each other perhaps in a waiting room after their job interviews waiting to hear who got the job as they're maybe starting to get bored Jones counts out loud how many coins he has in his pocket exactly ten they discover Jones puts the ten coins back in his pocket as the president of the company comes into the room the president congratulate stones announcing that he's a great fit for the position as Smith leaves the room disappointed here's something that he believes Jones who has ten coins in his pocket will get the job from this Smith concludes that the man who will get the job has ten coins in his pocket and that's our key proposition P right now it might seem that Smith even knows that P knows that the man who will get the job has ten coins in his pocket but there's a twist for some reason at the last minute the company ends up hiring Smith not Jones and unbeknownst to Smith he happens to have ten coins in his pocket as well so when Smith believes that the man who will get the job has ten coins in his pocket what he believes is true because Smith will get the job and Smith has ten coins in his pocket it's also justified because Smith has good reasons for thinking that Jones will get the job and that Jones has ten coins in his pocket but des Smith actually know that the man who will get the job has ten coins in his pocket it seems not Smith is wrong about who will get the job and doesn't how many coins are in his own pocket if Smith has a justified true belief in our key proposition but doesn't know it then the JTB analysis is wrong philosophers now use the label Gettier case for any story that illustrates the possibility of justified true belief without knowledge it turns out that there are many such cases often simpler than get ears original suppose that Smith wonders what time it is and glances at the clock on the wall which clearly shows the time as 3 o'clock looking at the clock is a perfectly reasonable way of telling time so Smith has a justified belief what he doesn't know is that this clock is broken and it's hands haven't moved in days but by chance it is exactly 3 o'clock right now does Smith actually know the time as he looks at the broken clock back in 1948 Bertrand Russell just used this case to illustrate the possibility of true belief without knowledge but looking back on it now we can say something stronger it's a case of justified true belief without knowledge it's a Gettier case in fact there is some even older Gettier cases in the history of philosophy the 8th century indian philosopher dharma torah tells a story in which a fire has just been lit to roast some meat the fire hasn't yet produced any smoke but the meat has attracted a swarm of insects a distant observer looks at the cloud of insects and stakes it for smoke and judges that a fire is burning at that spot Dermott hora suggests that this distant observer doesn't know that there's a fire burning looking back on this story we can use it as a counter example to the JTB analysis of knowledge if it doesn't work to analyze knowledge as justified true belief what does work you may have noticed that the getaria cases we've talked about so far have some features in common and you might think that we could take account of those features and add a simple patch to the JTB analysis to fix it up but as we'll see in the next two videos in this series the problem of deciding what to add the true belief to get knowledge turns out to be surprisingly difficult