so we're starting this philosophy series with the question what is knowledge now on the face of it that might sound like kind of a boring topic to start with you know I don't think many people are kept up at night worrying about the correct definition of knowledge like they might have questions such as whether God exists or what the meaning of life is but the definition of knowledge is a good topic to start with because it illustrates a lot of how philosophy Works uh when you boil a lot of these philosophical questions down they they ultimately just become the questions about definitions of things so if you think about moral Philosophy for example a theory such as utilitarianism is essentially just a definition of what good is and so by looking at this story of the various definitions of knowledge that the field prop over the years and the issues with these definitions it's a good way to illustrate how this philosophical game is played it illustrates the difference between a good definition and a bad definition uh it shows us how we can critique philosophical definitions in theories and it's just a good round introduction to philosophical reasoning in general so let's do some [Music] philosophy so uh before we get into the definitions of knowledge themselves uh let me first explain how this game is played um the classic way definitions work in philosophy is this idea of necessary and sufficient conditions now of course there's many philosophers who reject this entire conception of language such as Vicken Stein and this is probably more in line with my own personal view but at least for the purposes of today we're going to play the game according to these rules we're going to try and provide a definition of knowledge in terms of necessary and sufficient conditions so according to these rules a good definition will contain conditions where each individual condition is necessary for knowledge and taken together all these conditions will be jointly sufficient for knowledge now what that means in simple terms is that everything that's an instance of knowledge will fit our definition of knowledge and everything that fits our definition of knowledge will be an in of knowledge if you think about it in terms of V diagrams what that looks like is two circles that overlap perfectly if we include conditions that aren't necessary then our definition will be too narrow because it will rule out things that are knowledge if our definition includes conditions aren't necessary for knowledge then our definition is going to be too narrow in other words there's going to be things that are knowledge that are definition exclud includes on the other hand if our conditions aren't sufficient for knowledge then it's going to have the opposite problem our definition is going to be too broad or in other words our definition our definition is going to say things are knowledge when they are not knowledge so one final thing to mention before we get onto the definitions of knowledge themselves and that's to specify the kind of knowledge we're defining because there's many different types of knowledge so you've got ability knowledge that's knowledge of skills such as knowing how to ride a bike or knowing how to juggle when we're talking about the definition of knowledge we're not talking about the definition of ability knowledge you've also got acquaintance knowledge which is knowledge of a person or a place so in the way you might know your home City well or you might know your best friend well when we're talking about the definition of knowledge today we're not talking about acquaintance knowledge either instead when we're talking about the definition of knowledge today we're talking about the definition of propositional knowledge specifically now propositional knowledge is knowledge of facts and it's sometimes called descriptive knowledge so my knowledge that I know that Paris is the capital of France or I know that 2+ 2 equal 4 these are examples of propositional knowledge and so when we're talking about the definition of knowledge going forward we're talking about the definition of propositional knowledge specifically so the classic definition of knowledge then is Justified true belief Bel and this is sometimes called the tripartite definition because there's three parts Justified true and belief and this this definition originated all the way back in Plato's dialogue Theus written I think in the 4th Century BC and uh this definition of knowledge this tripartite definition was generally accepted for over 2,000 years to provide both the necessary and sufficient conditions for knowledge on the face it the tripartite definition Works quite well all of these conditions do appear to be necessary obviously knowledge requires it to be true uh if you say I know the moon is made of green cheese then you you wouldn't consider that knowledge because it's not true so truth is necessary for knowledge likewise belief uh it just wouldn't make sense if you said I know that Paris is the capital of France but I don't believe that Paris is the capital of that just doesn't make sense so belief is also considered to be a necessary condition of knowledge finally justification it's this justification condition that that differentiates Knowledge from just the lucky guess so if I were to ask you how many moons does Pluto have now unless you're an astronomy nerd or whatever you probably don't know the answer but if you just had a a strong gut feeling that the answer was five you would be right but your belief that Pluto has five moons wouldn't be knowledge because you you don't have a justification for it so justification also appears to be necessary for knowledge so Justified true belief appears to work quite well as a definition of knowledge uh each of these conditions appears to be necessary for knowledge well actually I mean there's some philosophers who who argue that some of these these conditions aren't necessary like you can get into wacky definitions about truth or describe weird scenarios where somebody knows something but they don't believe it maybe it's subconscious or whatever but generally speaking Justified true belief is considered to be necessary for knowledge the juicy criticism and I'm of course talking about getia cases is arguing that the tripartite definition is not sufficient for knowledge so like I mentioned earlier the trip type Justified true belief definition of knowledge dated all the way back to Plato in the 4th Century BC and this definition basically went uncontested for over 2,000 years that is until 1963 when Edmund gettier described two scenarios now known as getia cases where a person has a Justified true belief that isn't knowledge in other words Geer described two scenarios that show Justified true belief is not sufficient for knowledge the first get a case goes like this two guys Smith and Jones are interviewing for the same job Smith hears the interviewer say I'm going to give Jones the job and Smith also sees Jones count 10 coins from his pocket so based on this Smith forms the belief that the man who will get the job has 10 coins in his pocket so they go through the interview but Smith gets the job and not Jones and then Smith looks in his pocket and by pure coincidence Smith sees he also has 10 coins in his pocket so Smith's belief here was justified it was justified by the fact that he heard the interview say he was going to give Jones the job and it was justified by the fact they saw Jones count 10 coins from his pocket what's more Smith's belief was true the man who got the job did have 10 coins in his pocket the thing is though we don't want to say Smith's belief he accounted as knowledge because it was just luck that he was correct Smith's true belief was formed on the basis that Jones would get the job and the fact that Jones had 10 coins in his pocket it was just luck that Smith himself had 10 coins in his pocket this shows that the Justified true belief definition is too broad because Smith had a Justified true belief but he didn't have knowledge this isn't one of geier's own examples but it illustrates the same principle so imagine you hear your phone go off you pull your phone out and you see you've got a message but you also see that your phone was on silent and actually the noise you heard was somebody else's phone who has the same ringtone so here your belief that you had a message was justified by the noise you heard and it was true you did indeed have a message but again the justification was irrelevant to the truth of the belief it was just lucky so again this is another example of a Justified true belief isn't knowledge geier's 1963 paper is about as groundbreaking As It Gets In philosophy which maybe isn't saying very much but anyway and since 1963 various philosophers have tried to propose new definitions of knowledge that avoid geti a cases and patch up the definition of knowledge such that it doesn't um include Gea cases come on so the first post getia definition we're going to look at is called the no false lemus definition and what this does it is it just adds an extra condition onto the tripartite definition so the new definition becomes knowledge is Justified true belief that is not inferred from a false Lema a false Lema is essentially just a false belief or a false assumption in an argument so going back to the original gtia case we can correctly say that Smith's belief Bel doeses not count as knowledge because it was derived from the false Lemma that Jones would get the job even though Smith's belief was true and Justified the no false list definition would say it's not knowledge because the justification was based on the false Lemma that Jones would get the job so by adding this extra no false lemas condition we narrow the definition of knowledge and we rule out Gea cases so it's an improvement however this no false lemur definition didn't last very long before people started coming up with similar counter examples to the Gea case where somebody has a Justified true belief that is not inferred from a false Lema but that nevertheless isn't knowledge so the classic example used to illustrate this is fake Barn County imagine a place called fake Barn County where the people create fake barns that look identical to real barns a guy called Henry is driving through fake Barn County but he doesn't know the locals do this Henry often thinks that is a barn when he looks at the fake Barns and these beliefs obviously aren't knowledge because they're not true the Barnes are fake Barnes however there is one real Barn in fake Barn County and when Henry looks at it he forms the exact same belief that that is a barn in this case his belief is true it's also Justified by his visual perception and most importantly it's not inferred from a false lemur so here Henry's belief is a Justified true belief that isn't inferred from a false Lema but like in the original GE here case we don't want to say Henry's belief here counts as knowledge because it's just luck that he was correct in this one instance after all every time he was looking at the fake BS he was forming the exact same belief and so he doesn't have the ability to tell real BNS from fake BNS yet the no false lemus definition says Henry's belief here counts as knowledge so what this shows is that the no false lemus definition is still too wide a bit like the original tripartite definition in other words the no false lemus definition is not sufficient either so we saw that the Justified true belief definition wasn't sufficient for knowledge and while adding this no false Lem condition improves this definition the no false lemus definition isn't sufficient for knowledge either so perhaps dayart can give us a better definition of knowledge well thear doesn't really intend this as a definition of knowledge per se but his approach to knowledge in meditations ruls out both geter cases and fake Barn County snipers for dayart something only counts as knowledge if it's absolutely certain if it's rationally impossible to doubt and so this approach is sometimes referred to as infallibilism applied to the fake Barn County case there's all sorts of reasons why Henry could potentially doubt his belief that that's a barn for example Henry's eyesight might not be 100% accurate or perhaps Henry's mistaken somebody's house for a barn or maybe Henry's actually in bed and dreaming that he's looking at a barn and so his belief is false or maybe Henry's taking a bunch of drugs I don't know and he's just hallucinating barns in any case these are all potential reasons for Henry to doubt his belief that that's a barn and while these might not seem particularly likely they're at least possible and if they're possible there are potential reasons for Henry to doubt his belief so according to infall bism Henry's belief doesn't count as knowledge because there are potential reasons to doubt it Henry's belief there is a barn is not certain it's a similar thing with the getia case there's all sorts of reasons why Smith could doubt his justif ation for his belief for example Smith could have misheard the interviewer or again Smith could be dreaming or hallucinating and so again infallibilism would say this isn't knowledge and so at first glance infallibilism seems to be an improvement on both the Justified true belief and no false lemons definition because where these these definitions say uh aren't sufficient they say that Henry's and Smith's beliefs are knowledge when they're not infallibilism correctly says that Henry's and Smith's beliefs aren't knowledge because they're not knowledge however whereas the Justified true belief and no false Lemma definitions were too broad in their approach they're not sufficient in philosophical terms infallibilism faces the opposite problem it basically rules out anything as knowledge and so it's too narrow in its definition of knowledge it seems obvious that I do know all sorts of things for example I know that 2 plus 2 equal 4 that Paris is the capital of France and that Plato was a Greek philosopher but there are all sorts of reasons why I could potentially doubt these beliefs for example I could have been the victim of some wacky conspiracy where everybody was lying to me about Plato being Greek and actually he was British or something now even if even if that doesn't seem particularly likely it's at least possible and so it's a potential reason to doubt my belief that Plato was a Greek philosopher and so according to infallibilism I I don't know this we can come up with weird scenarios to to to doubt Prett much every belief even something as fundamental as 1+ 1 equal 2 you know it's it's logically possible that an evil demon is just manipulating your mind and making you think that 1+ 1 equal 2 when actually 1+ 1 equal 3 now again not saying that's particularly likely but it's least possible it's a potential reason to doubt your belief and so according to infallibilism you don't know that 1 plus 1 equals 2 but this just seems ridiculous because clearly we do know all sorts of things and and so if we're to maintain any reasonable understanding of knowledge we're going to have to reject the infall definition it seems that certainty or the impossibility of Doubt is not a necessary condition of knowledge the next Contender for a definition of knowledge is virtue epistemology now this is a broad category like infall but in general virtue epistemology definitions draw a parallel between moral virtue and intellectual or epistemic virtue so let's start with the case of moral virtue first an act of moral virtue achieves a virtuous outcome so let's say you help an old lady across the road now that is a virtuous thing to do but is it an act of moral virtue if the only reason you help helped the old lady across the road was because you thought you she'd give you some money presumably not and so for something to be a proper Act of moral virtue it has to not only achieve a virtuous outcome but it has to achieve The Virtuous outcome because of the moral virtues of the person committing the action virtue epistemology says a similar thing about knowledge it's not enough for a belief to achieve a virtuous outcome I.E be true it has to achieve this virtuous outcome because of the intellectual Virtues Of The Believer so intellectual virtues are things like caring about the truth thinking rationally and so on and so applied to the Gea case we could say that Smith's belief while true and while achieving a virtuous outcome is not an act of intellectual virtue because the truth of the belief is not a result of Smith's intellectual virtues the truth of the belief was a result of luck as such virtue epistemology would correctly say that Smith's belief doesn't count as knowledge in the same way that helping the old lady across the road to get money wasn't a proper Act of moral virtue Smith's belief that the man who gets the job has 10 coins in his pocket while true wasn't a proper Act of intellectual virtue because it wasn't true for the right reasons nailed it Ernest Sosa illustrates this idea of intellectual virtue with a nice analogy to do with archery so what is a good shot in archery well firstly a good shot in archery is accurate it hits the target but an accurate shot in archery doesn't automatically mean a good shot because the arrow might have just hit the target through luck and similarly a true belief doesn't automatically count as knowledge because the truth of the belief might have been lucky as well the Geer case is an example of this instead what makes something knowledge is that the belief is true because of the person's intellectual virtues in the same way that a good shot in archery Hits the Target because of the Archer's skill and not because of luck by requiring this link between the truth of the belief and the way it's formed or intellectual virtues virtue epistemology rules out Gea cases without going full infallibilism and basically ruling everything out as knowledge so according to Virtue epistemology I can know that Paris is the capital of France or that 1 plus 1 equal 2 or that Plato was a Greek philosopher even though I can't be 100% certain of these things as long as they're true and I arrive at these beliefs via my intellectual virtues because of my intellectual virtues then they do count as knowledge but as always with these definitions of knowledge there's always a counter example that you can use to critique the theory and in the case of virtue epistemology the one I've got in mind is is the example of children and animals so typically we do think that children and animals can possess knowledge for example a dog might know its name or a dog might know that there is food in the bowl likewise a toddler might know that a dog has four legs for example but it's hard to see how a toddler much less a dog could possess intellectual virtu such as caring about the truth or even thinking rationally so according to virt epistemology children and animals can't have knowledge and yet we typically think children and animals can have knowledge so virtue epistemology is perhaps still too narrow a definition perhaps epistemic virtue or intellectual virtue is not necessary for knowledge and actually and actually this children and animals objection can be extended to all the other definitions of knowledge we've looked at so far uh for example even Justified true belief it's hard to see how an animal could justify its belief or how a toddl could justify its belief and yet again we think they have knowledge um it's certain that there's Winkles in the Shell given that maybe some shells don't have Winkles anyway I'm getting bogged down in that example the point is I don't know what the point is actually anyway the next definition is is reliabilism so one way we can get round this issue is by doing away with uh the condition of justification or intellectual virtue and replacing it with something like formed via a reliable method what we mean by a reliable method here is one that reliably produces true beliefs so if your eyesight is 99% accurate then that would count as a reliable method or I don't want to talk about newspapers because they're not very reliable if hypothetically there was a newspaper that was reliable then and it it it printed the truth then uh that would also count as a reliable method if you formed your belief on the basis of this hypothetical newspaper what's important here is that reliable method doesn't require a justification as long as something produces true beliefs in a reliable fashion then it counts as reliable method even if you can't justify it or explain how it works so our new definition of knowledge could be something like knowledge is true belief formed via a reliable method and the advantage of this definition would be that it allows that children and animals can possess knowledge for example let's say a baby has parents who are knowledgeable and tell it the truth and these parents tell the baby that Paris is the capital of France and the baby believes the parents and believes that Paris is the capital of France well in this case the baby's belief does count as knowledge even if the baby forgets that the parents told it it so it can't justify its belief it still has this belief and the belief was formed via a reliable method I.E the parents and so it does count as knowledge and you can run a similar story with animals so a dog for example let's say has good eyesight and good memory well these could count as reliable methods and so a dog can also possess knowledge even if the dog can't explain how it got to that knowledge or it can't justify its knowledge as long as those beliefs were formed via a reliable method then this definition allows that these beliefs do count as knowledge but it's never that simple with these definitions of knowledge and in this case you can use the Getti a case to argue against reliabl ISM because we could say that Smith's belief that the man who get the job has 10 coins in his pocket was formed via a reliable method let's say that Smith has 100% perfect eyesight when he saw Jones count 10 coins from his pocket and let's say the Smith has 100% perfect perfect hearing when he heard the interview will say I'm going to give Jones the job well in this case Smith's belief that the man who will get the job has 10 coins in his pocket was formed via reliable method and if you remember it turned out to be true but for the wrong reasons it turned out to be true because Smith himself had 10 coins in his pocket and so we've gone full circle here we're back to square one back to Getti a cases and we don't have a definition of knowledge so we've come full circle at the start of this video we set out to provide a definition of knowledge in terms of necessary and sufficient conditions we started with the Justified true belief definition but we saw how getia cases showed that this definition wasn't sufficient then we looked at four post getia definitions that seek to patch up this definition we looked at the no false lemons definition we looked at infallibilism we looked at virtue epistemology and finally we looked at reliabl ISM however with each of these alternative definitions we found counter examples that disproved these twoo either showing these conditions weren't sufficient for knowledge or that they weren't necessary there's way more to this definitions of knowledge debate than I've covered here but the thing is with academic philosophy is it can get very pedantic uh very quickly but uh suff to say that the Defenders of reliabl ism for example or virtue epistemology wouldn't leave the debate there for example we could have gone into how Goldman def defines a reliable method in such a way that rules out Geer cases or we could have done a bit more of a deep dive into saa's virt epistemology and look at how Sosa's definition of intellectual virtues allows that children and animals can possess knowledge the point though wasn't to argue that any particular definition of knowledge was correct really the point was more to illustrate how this philosophical Game Works to illustrate how conceptual analysis in philosophy works so we looked at this idea of necessary and sufficient conditions and how this is what constitutes a good definition we looked at how we can critique these definitions by coming up with counter examples or thought experiments that show either these definitions are too broad I.E they are not sufficient or they're too narrow in that they include conditions aren't necessary so that about does it for definitions of knowledge thank you so much for watching uh I hope you learned something if you have any questions let me know in the comments uh or if you have your own definition of knowledge that you think will settle this debate once and for all let me know in the comments if you wanted to research this topic a bit further you can go I'll link the page on my website that talks about definitions of knowledge in more detail and um I can recommend a few books as well obviously my own book that provides a good uh slightly more in-depth overview perhaps of these different definitions of knowledge but if you're looking for something a bit more um academic perhaps I can recommend an introduction to contemporary epistemology by Jonathan Dancy I don't know who this guy is on the front but he looks like Blackbeard so you can get that book um I also I'm going to link uh gettier's 1963 is Justified true belief knowledge paper in the description uh it's not a particularly long one so if you want to engage firsthand with some philosophy then be my guest then the other primary sources I mentioned not really great for definitions of knowledge cuz they cover a lot of other things but I can recommend them uh Plato's Theus I can't say I've read the whole thing but Plato's dialogues in general are quite readable so that might be worth picking up and uh the other one I mentioned the classic dayarts meditations now this is really a page Turner as far as philosophy books go so I can I can thoroughly recommend decart's meditations it's it's a real classic um so yeah that about does it for this episode thank you so much again for watching and uh yeah I see you in the next [Music] one