Kant 1: Synthetic A Priori Knowledge

okay welcome to this set of lectures on the philosophy of Immanuel Kant we're going to be looking primarily at the views expressed by Conte in the critique of Pure Reason which he writes in 1781 and also at the way he puts it in the prologue omona to any future metaphysics so we're primarily going to be looking at Kahn's response to Humes problem of induction and his transcendental idealism so Kant describes himself as being disturbed by his from his dogmatic slumbers by reading Humes argument so here's kahn thinking that reason can show us science can show us the necessary truths about reality the way things have to be and hume comes along and presents a very detailed argument that this is just nothing more than something akin to classical conditioning and that really we don't discover necessary truths by experimentation or by reason we rather just describe psychological truths so this is the way that Kant expresses Humes conclusion so he says experience can teach us that something is the case but it cannot teach us that it must be the case so content perfect agreement as long as you're an empiricist and you think that science is the only way of knowing about the world then we'll never be able to figure out anything necessary or figure out the way the world has to be always and everywhere we'll rather just learn that it is this way here and now and so he's in perfect agreement with Humes conclusion insofar as that's what you get from empiricism but of course contests disturbed by this because science does claimed to discover necessary truths about nature that it does claim to discover the way the world must be everywhere and always so that when we know that water boils at 100 degrees Celsius at sea level with the density of 1 we know that that is true everywhere and in China in Australia it's even true on the moon if you could get water with density 1 and at sea level the same pressure then it would boil at 100 degrees Celsius so this is supposed to be a universal truth about the world we live in and yet Hume comes along and shows that there's a deep problem with thinking that way if you take empiricism seriously so now even worse according to Kant is that Hume showed that human beings are essentially irrational reason doesn't have any real role to play on Humes theory you may recall that for Hume the role of Reason is just to analyze ideas and to ferret out definitional relations between these ideas so that we can know that two plus two is four with certainty but all that is is knowing some definitional truth about the way that our ideas are related to each other and it doesn't tell us anything about the way the world is so we never discover anything about the world we live in with the use of reason it's always the emotions and this kind of conditioning that's driving us and reason is up there making up stories so to speak telling itself that it's these connections are necessary and that the world works in a certain way but that's not the job that reason has nor is it one that it can even perform so Kant is very disturbed by this because Khan sees human reason as the source of the value of human beings and so if you studied some of Kant's ethics so if you look at his view about the categorical imperative and etc you'll see that Kant thinks that it's rational autonomy the role that Reason plays which gives human beings their dignity their value and so he really sees human beings as special as occupying a special place in reality and it's due directly to their rational capabilities that they have this special place so if Hume is right that we are no more than driven by instinct and reason is ineffectual and plays this very limited role of merely analyzing conceptual definitions then reason can't play the role that Kant wants it to so he really is awoken from a dogmatic slumbers where he comes to realize hey look I need to give a response to this argument because if it's right then the project that I have and that I take to be the most important job of philosophy can't be completed so that's what Kant this is really personal for him in that it's directly an attacked on the things he holds most valuable and can't actually chastises people in his contemporaries for not taking human seriously as they should so Kant disagrees with Hume he wants to try to show that we can have knowledge about the way reality is based on reason but he realizes that you can't just dismiss Hume with a brush of a hand as someone who holds these crazy fanatical views that reality is unconnected for all we know but you've got to actually provide some kind of response and kind of arguments okay so the view that try that Kant comes up with is what he himself calls transcendental idealism and we'll talk more about why it's called transcendental idealism as we go through this set of lectures but for now just recognize that that's what Kant called his own view and he agrees with Hume as I've been saying previously that we can't learn the causal relation is necessary in universal from experience so he agrees that from experience we'll never derive the necessity of the causal connection but conte wants to point out that hew did not show that we can't have AA priori knowledge at all in fact Hume wasn't concerned to show that since he just kind of takes it for granted that a priori knowledge is useless for figuring out the way the world is and this is understandable because Hume is an empiricist and he's primarily making an argument from within empiricism namely that if empiricism is true who than these various other things follow so Hume really didn't give at least in the sections we looked at he didn't really give an argument against the possibility of our priori knowledge so Kant wants to try to rectify this and he's going to say look you can take Humes argument at face value and what that shows is that we don't get necessity from experience but it doesn't automatically follow that we don't get necessity from reason now of course humor Gries to some extent that you get necessity from reason because human defines a priori just as the relations of ideas and so certain ideas are defined in such ways that you can't deny them without contradiction and Hume is happy to call that a priori something that's knowable independently of experience but what Kant wants to do is to argue that there's a more heavy-duty notion of AA priori knowledge which is around which can do some work for us so for for Kant is going to say yes there is this kind of thing that that Hume is talking about this a true by definition kind of thing and that does give you a kind of necessity but there's also another kind of AA priori knowledge which is something which is knowable completely independently of any kind of experience whatsoever so and this kind of a priori knowledge is not merely definitionally true so of course human wants and say yeah yeah yeah we can have knowledge completely independently of experience like when I know that all bachelors are unmarried males I don't need to have any experience with bachelors all I need to do is analyze my concept of bachelor look it up in the dictionary figure out what the concept means and then I know that of course it's true that they're all unmarried male so that's you get a kind of completely independent of experience kind of knowledge but Kant wants to say look there's we can have more than that so Kant wants to show that there is this more heavy duty notion of the AA priori which is essential and that once we understand this heavy-duty notion of the up priori we can provide an argument which answers Hume so that's going to be the project that we'll be working on and there really are two parts to this project the first is the kind of technical diagnosis and statement of the problem of induction as given by Hume and cons technical answer to that and then second there is the overarching philosophical view of transcendental idealism which makes this answer possible and has certain consequences for views about reality in the nature of the mind so the first thing we're going to look at is Contech Nickel answer to Hume as the development of what we call synthetic a priori knowledge with this real heavy-duty kind of AA priori knowledge that cons wants to introduce and this the synthetic aspect of it which will come to so that's going to be a bit technical and then after we're doing that we'll turn to just generally looking at transcendental idealism and the philosophical background in theory that Kant brings with them okay so let's go ahead and get started now we'll begin talking just about the AA priori and the way that Kant wants to talk about the AA priori it's a bit difficult for us to put ourselves in the right frame of mind so I like to start with an analogy suppose that I told you that there were in fact 25 people located in a room on the second floor of some building so you just take this as given this this you know is true there are these 25 people located in a room somewhere on some building on the second floor now is there anything that you could come to know about this particular room so take a second and think about that well if you think about it you'll come to see that there's quite a bit that you could know about this room without having any experience of who these people are or where this room is or anything you could know some surprising a surprising amount of information about it so for instance you could know that something about the size of the room well there's got to be enough space to fit the 25 people it can't be the size of a shoebox for instance now you don't know the exact dimensions of the room but you know that there must be enough space for each person in that room to be located at one position and that none of those people in the room are going to be located at the exactly the same position so even if they're sitting on each other's laps they're not going to be located at precisely the very same place in that room so there's got to be enough space in there to hold them all they have to be located in certain positions now I can't know who's sitting where who's standing where but I can know that each and every person will be located at one particular place and only one particular place now I can also know something about what the room is made out of so if it's on the second floor and it's supporting the weight of these 25 people then I know that it's not made out of shaving cream for instance or pudding pops popsicle sticks I don't know if it's made out of wood or concrete I haven't told you anything about that but we can know some general structural facts about this room given that it's on the second floor of a building and it has something like 2,000 pounds conservatively estimating each person the way something like a hundred pounds at minimum we're going to get something like 2,000 pounds given that there's 25 people in this room so we have to know that it may have some kind of sturdy material that can support the weight of those people so this is noticing I'm you're just relying on what you know to be true and acting a question which is given that we know that this is in fact true what would have to be the case in order for this fact to actually be true and that's what Conte wants to do in his argument is he wants to start with something that we know is true and then ask the question what possible conditions of the world would have to actually be present in order for this thing that we know is true already to be true so he wants to ask about the conditions of possibility so given that we know this is true what does that tell us about the way things have to be the difference of course is that he's not talking about a room as considered as some object but he's can talking about our experience of the room so you have to recall all the way back from the Descartes section of these lectures when Descartes gave his argument from dreaming and the argument from hallucination or misrepresentation in general everybody in the modern period for the most part accepts that when we have our normal everyday experiences of the world we don't come into contact directly with the physical objects that exist but rather we have to go through some process of inference we infer that those objects are out there and that they are the cause of the experiences that we have so in the same way when you watch an image on a TV screen you infer that the cause of the image on the screen is in fact the things which are represented so if you're watching The Today Show with Kathie Lee and Hoda Kotb and you see their images on this screen there's Kathie Lee sitting there there's Hoda right next to her what those aren't the actual people you're observing those are the images of the people and you just assume or infer if somewhere to ask you you would say oh well if someone said well hot why are those images on the screen there you would say well because there's a camera there's Hoda and Kathie Lee there and the images are being transmitted they're being captured by the camera I mean transmitted to me and reproduce on this screen you make an inference about the cause of the images on your screen so to these general this general line of philosophy holds the when you're looking at a tree in real life when you're awake looking at the tree that that's in effect being presented with an image in the mind which represents the object the actual material object and that just as when you look at the TV you don't have access to Hoda or Kathie Lee you have only these images so - in normal sense perception you only have access to these kinds of images so this is what Descartes thought and then you make an inference that the objects really exist out there and they cause your experience he needs to invoke God in order to make sure that inference works and and then you come along with lark Locke who accepts this view as well it says matter material objects are something I know not what that exists out there as the cause of the kinds of representations that I have Berkeley comes along and argues that there's no good reason to believe in this matter and so argues for a kind of idealism so that all we have evidence for are these mental things and if you're an empiricist you should reject the existence of material objects altogether Hume comes along and says well this question isn't really a meaningful question since but we can't answer it with the methods of empiricism so we should just we'll never know the answer to the question we should give up on it and focus on what we do know about which are the kinds of experiences that we have and Conte is now coming along and suggesting well yes let's follow that methodology let's start with the thing that we know about so we may be dreaming right now and you your normal sense experience may not actually correctly represent the world outside of you but the one thing that you know is true is that you have this kind of sense experience so if we were to examine the actual experiences we have examine the kind of experience of the world that we have each and every second we're awake we could try to reverse-engineer the conditions which would make that experience possible so you're sitting here you're looking at a table you know that you have this experience and Kant wants to ask the questions how could you possibly have that experience what would be the case what would have to be the case in order for your experience of a table an ordinary experience of a table in order for that thing to be the way that it is what would have to be true so in a way this is just like what we were doing with the room we we know we have some facts which we know is true and then we try to figure out well how could that thing be true except for that kontin's going to be talking about the very structure of his experience so he's gonna think about the experience he has of the world and then ask the question how could I possibly have that kind of experience how could our experience be the way that it is so for example think about your experience look at a table for instance or some ordinary physical object what happens to be around you and don't think about the table the object but think about your experience of that object put yourself in the frame of mind of you know I'm just having an experience right now the table looks a certain way to me examine it very closely what can you note about it Khan thinks that every time we have an experience we pay close enough attention to it we'll come to realize that the experience is always presented as occupying a certain region of space so look at the table and you say well yeah the table is presented from my point of view as being a certain distance from me in occupying a certain table --is-- area of space so now if I were to walk around the table I would see the very same table from these different points of view and I can sort of imagine what the table would look like if I were to walk around and see it from the other side if I were to hover above it and see it from the top or if I were to crawl underneath it and see it from the bottom or squint one eye or look at it from a diagonal sort of looking up and so on and so forth so any way that the table is going to be presented to me is going to be presented as occupying some definite location in space and of course the same thing holds true of time every experience of I every experience I have is always after some other experience and located before some future experience so that I have this constant kind of streaming thing where every experience that I have as I move my body around in the space performing comes either before or after certain other experiences and of course we're very good at order ordering our experiences temporally for instance I had breakfast this morning a bowl of cereal and I can tell that that happened before right now so the cereal came before am I talking about Conte and this experience is coming before the experiences I'll have later this afternoon when I take care of some other business and go run errands and etc so that I have this constant ordering of one experience after another and I'm pretty good at knowing when things happen in my own stream of consciousness now of course this is sort of a trivial point yes every time you see something it's located somewhere but Kahn's going to make a lot out of this point so he asked us look now try to imagine having an experience of an object without that object being located any particular place can you do that now of course you might have been tempted to think yeah but the answer is no so if you were thinking look I'm just imagining some table floating in space a pitch darkness around it just the table right there but even so you're picturing the table as being located a certain way in your visual field so either dead on either you're above it or below it you're off to the side it's all very far off in the distance like a microdots and there's vastness of space around it or it's very closed up so you're always picturing the table as being located somewhere so if this is true then we have our first demonstration that there really is knowledge that's a priori that tells us about the way the world must be and isn't merely deaf initially true so we can know without having any experience at all that whenever we do have experience the objects that we experience will be located relative to me somewhere and in some temporal sequence of past and prior experiences so this is sort of similar to when we're talking about the room and we were asking ourselves what do we know about the people in the room without having ever met them or seeing them well I can't tell you where Joe is or Bob is or Doug or Sally or whatever but I can tell you that wherever they are they're going to be when I open the door I'll see them as located somewhere in that room and in fact this is necessarily true of any object that I will ever see any object that ever is seen by me or by you will always occupy some definite region of space and will be presented to me in a certain way this is what Conte means when he says that space and time are the conditions of all possible experience in order for there to be any experiences at all there has to be space in order for those experiences to be located in so this is a precondition of experience and that's important because it's not the kind of thing that you learn from experience and notice it's not as though a baby is crawling around in the world when its first born and coming to learn Oh objects are located in space but rather Kant's idea is in order to be able to see an object at all there has to be space for it to be located so this is something which makes possible the very having of an experience it's not something that you learn from experience so but objects being located in space is not something that's merely definitionally true of being an object so it's not as though object the word concept is defined in terms of being located in space so this is something that you can know without any experience in fact it's what makes experience possible and it's not merely definitionally true it's necessarily and universally true and it's something about the way the world is objects are located in space that's something that we can know a priori in this real heavy-duty sense of the word which is going beyond Humes idea that these things are merely relations of ideas so contests here suggesting there's more to the ahh priority than relations of ideas there's these kinds of facts that we can know about the structure of our experience which in effect are reverse engineering the way that our mind puts experience together for us so we're not we're just studying the way the mind works and looking at the things that it produces well approaches these experiences well how could it do that well first of all there it'd have to be some space that these experiences could be located in and there has to be this unit of time by which we can order these things and so we can infer from this that space is an S acute necessary condition of any possible experience and we can know with absolute certainty that whatever experiences we do have they will all take place at some time and at some particular place so this is converse demonstration that we can really have some substantive our priori knowledge knowledge that goes beyond merely being definitionally true so as I just said concludes that there is what he calls pure or a priori knowledge now what Kant is trying to capture by calling a pure a priori is the distinction between this kind of a priori knowledge knowledge that really is completely independent of any pot any experiences at all no particular experience ever taught you that objects are located in space but rather this is just something which you know must be true in order for experience to exist at all and that's different than for instance your knowledge that if you undermine the foundation of a building the building will collapse so that's something that you don't need to go out and undermine the foundation of some building to find out if you do that that it will in fact collapse you can know that independently of experience but that's not purely independently of experience there because it's in fact you've learned based on past experience that undermining the foundation of a house will result in it falling down so you don't need to go do it now because you've already learned that fact and that's a kind of you might say well that seems aa priori because there's no it's you know it independently of going and doing it but it's not the pure kind of a priori because there was some kind of experience in the past that's playing a justifying role in your deduction so when Khan talks about the pure a priori he means the kind of stuff in which no particular experience plays any kind of a justification role in the in the deduction so you can know that space is required in order to have experience with no particular experience serving as a premise in that argument now that's again just what I was saying a moment ago that's why he terms the notion the pure a priori there's no particular experience that it depends on and it's important to notice though that well you get the concept of object by seeing them and space by having experiences and so on so you might think look you know experiences playing some role here but cut is making this move that the experience is required merely for you to have the concepts in play you don't need to use any experience though in making your actual deduction from the nature of experience in general experience with a capital e generally experience so you start with that which you've acquired of course by having particular experiences but no particular experience no particular seeing of a table or chair or watching some sequence of events in the world it's playing any kind of role in justifying your inference from the notion of experience in general to the notion of space being necessary and that's what he means by the pure a priori and again this is because these things are rather the preconditions for any possible experience at all that are the things which must be true in order for experience to exist now notice that this is something which is necessary every experience is one that's going to be in space it's impossible to even conceive of an experience which isn't located somewhere in your frame of view it's not possible to have an experience without space and it's also something that universally true is true of all experiences everywhere so it doesn't matter where you have these experiences if you go to the Moon and orbit around it the moon will still appear to be located somewhere in your visual frame of reference if you go to Pluto and etc etc so you get the picture these so context necessity and universality as the mark of the AH priori now so we've got to muddy the waters here in order to get Khan's full story out on the table because we have one distinction on the table already the analytic excuse me the opry or E and the a posteriori and we need to introduce a new distinction that Conte introduces what it calls the synthetic and analytic distinction so an analytic truth four-pronged is one that's just true in virtue of the meaning of the words themselves so this is the relations of ideas idea you've just given a new spin so for Kant this the analytic relationship is one of conceptual containment so that he really thinks of the concept so now we're talking about this mental thing the concept the concept of a bachelor contains within itself the concepts of unmarried and male put in a certain relationship so that the idea is I'm a week we can we can just say as modern people well its meaning entailments here these are definitional things but can't really thinks of it as a containment relationship and so to be technically correct you would say the concept Bachelor contains these other concepts because this is the way that Conte talks about it but it's just another way of capturing what Hugh meant by the relations of ideas these things just like Hume said they don't add anything new to our knowledge you don't learn anything new about bachelors by being told that they're unmarried males if anything you learn what a bachelor is but you don't learn anything about bachelors so this this is the idea of containment when you examine the concept you just see that it already has within it the concepts of unmarried and the concepts of male synthetic truths on the other hand are ones where there isn't this kind of conceptual containment relationship so when you think about the sentence the all bachelors are messy you look quote-unquote inside the concept of Bachelor and you see it contains unmarried and male but it doesn't contain anything in there about messy so you could fully master the concept of Bachelor you could know everything there is to know about what a bachelor is and still not know whether it's true that all bachelors are messy because there's nothing contained in the concept which would tell you that now when someone tells you that bachelors are in fact messy what they're telling you to do is to synthesize a new fact and that's why I can't calls these synthetic truths so and when you take a synthesis you take two things which we're not joined before and you join them so you have your concept of bachelor and it contains these things just by definition just by being the kind of concept that it is and when someone tells you that bachelors are messy they're telling you to take your concept of a messy person and to put it inside the concept of a bachelor so that now it's in there but not as part of the definition but as something which is new so you would star it for this is something new about bachelors which you didn't know before so you're making a new fact join the concept of messiness to the concept of bachelors so analytic truths are ones what you just analyze the concept and see whether it contains these various other concepts as part of its definition and it doesn't tell you anything new and synthetic concepts are by their definition they're adding to what we know about these things so you don't know but by just having the concept you don't know our priori whether bachelors are messy you need to go and check some bachelors and then if you find that all bachelors are messy you can join the concept of messiness to bachelorhood and if you find that they're not then you would dis join them you would say they don't belong together so this is the way that Hume taught about all of the opry orion ah posterior a stuff you said look this is it you have those things which are true by definition and don't add to our knowledge and you have those things which are are not true by definition and do add to our knowledge and that's all that you give and now what Conte is done is to make a four-way distinction with using two sets of distinctions so to put all this together hume claimed that something was aa priori when if you denied it you get a contradiction so Hume says look all we mean by the operatory is that you if you deny it you get a contradiction and of course when you have definitional relationships that turns out to be true if you deny it you get a contradiction so using this he divides everything into relations of ideas which are necessary and matters of fact which are contingent and cons has just relabeled this division the analytic synthetic division so concepts look ok so you have those two categories but you also have these other two categories you have the opry Ori which is also analytic so remember a priori for cons is meaning something more substantial more heavy-duty so a priori truths are ones that are necessary and universal they tell us how the world actually works and you could also join that with a truth that's analytic so all bachelors are unmarried males is in fact something which is true by definition and also necessary and universal so those two things go together for Conte being analytic and being aa priori and it's true that all analytic truths are operated for cons because it's true that these definitional and relationships hold up necessity and you have universal characteristic so all bachelors are unmarried males it's impossible for there to be a bachelor that's not a married male ok but on the other hand there's you can see a category of being analytic in our posterior truths which are true by definition and really don't tell us anything new about the subject and but also ones that are discovered by experience and cotton says look you know that's there's none of those this is something which is in become interesting in later years and in fact there are some for instance one of my professors in graduate school saul kripke is famous for suggesting that scientifically discovered definitions like water equals h2o we're talking about the essence of an object the count is a kind of definition and also something which is the posterior II discovered by experience and so some people have said well what Kripke is talking about shows that there are analytical posteriori truths but that's a different question for a different day we talked briefly about trip keys views in the final lecture of the class we look at some contemporary philosophy of mind but we'll put that off till later the Khan says no way that doesn't make sense ok but there is a synthetic a posteriori which is the kind of judgments to add to our experience like that pizza is delicious dogs bark and the you know taxes are a certain rate cetera and also stuff which is neither necessary nor universal so the synthetic a posteriori adds to our knowledge and it's learned from experience but there's one category here which has been overlooked so far Khan thinks and that's the a priori so synthetic means that it adds to our knowledge about the world but the AA priori bit tells us that this is something which is necessary and universal and is a truth about the way the world works now Hume of course denied that there were any synthetic a priori he says it's either everything is either synthetic or posterior E or analytic a priori there's only two categories and cons answer here is to say no there's if you think about these things in a different way then you can see that there's a third category the synthetic a priori and what's interesting there is that you have a combination of the rationalist view that knowledge is gained by experience because you have the operatory doing some real work but you combine that with the empiricist idea that you have to learn certain things from experience and soak on things that you get a kind of symbiosis between the two to major schools and epistemology that have been battling and one of his great achievements in Khan's own mind was that he was able to provide a kind of philosophy that really used the best of both of these two kinds of methods so Humes mistake was that he didn't recognize that there was a kind of real a priori knowledge which could add to our knowledge about the way the world works that we could actually do metaphysics in the sense that we could figure out how the world really is using reason and then that would tell us something new about the way the world is so let's pictorially represent this and this is just going to be the same stuff we were just talking about but using a graph so that we can see what's going on here so on the top up there we have the opry Ori and the AH posterior E and running down along the sides here we have the analytic synthetic distinction so it gives us four categories so one category is the AH priori analytic those are things which are true by definition they do not add to your knowledge they are necessary they can't be false they are universal they're true everywhere and at all times so there we have like things like all triangles have three sides true by definition and etc so on the other corner of the diagnose air we have our synthetic posteriori truths these things do add to our knowledge they're not merely definitionally true learning that dogs bark is learning a new fact about dogs and in fact I famously when I was a kid I didn't know what sounds certain animals made so for instance what sound does a giraffe make I didn't know and I sort of just thought that they would they were named after the sounds that they made so a giraffe would go giraffe or something like that in some animal II kind of way and of course that turns out to be wrong but the way I discovered that it was wrong was not by learning what a giraffe was I already knew that but it was learning actually going to a zoo and observing giraffes and reading about them and having experience with these animals so those things tell us something new they add to our experience they are neither necessary nor universal not every dog barks there are some dogs that don't bark those are called good dogs just kidding they're not every Apple is delicious some apples are bad and etc so you have those two categories which are just Humes categories so human would have called the top left one the relations of ideas and it would have called the bottom right one the matters of fact and Cantus just rework this into his own framework at calling one the analytic a priori and the other one the synthetic posteriori now the analytic a posteriori section we already told you people can't in particular argued that there was no such distinct the category is empty that there's nothing in there other people have wondered whether that's true but we're going to leave that aside for now the big question is is there anything in the synthetic a priori category now notice there's one thing which is missing from our list if you think about all the stuff we've been talking about that Hume was interested in there's one set of facts which we know to be true which is not represented up here and that is math in the form of arithmetic but mathematics in general so notice not geometry geometry we know is already belongs in the analytic a priori category but what are we to say about mathematics well Shoom would have put it in the analytic a priori category for instance knowing that seven plus five equals twelve according to Hume it doesn't tell you anything new about the number seven and five to find out that their sum is 12 what that tells you it's just part of the definition of what it is to be 12 what it is to be plus what it means to be equals all these things are just in or defined in such a way that it just comes out as definitionally true of the sentence seven plus five equals there's no other way that's like saying all bachelors are users only one way to complete that unmarried males so 212 here would just follow from the definitions of the terms employed so conte doesn't think that that's true he asks us to consider very large numbers like for instance what is the sum of one four one three one six nine nine five eight and seven five nine five eight six seven 73 well if you're like me you don't know what the sum is you know that there's some number which is the sum of those two numbers but what it is I don't know but surely I understand what each number on the left-hand side is I know what 1 million 116 or whatever I said is whatever particular number it is I know what that is but yet I don't and I know a plus and equals mean but all that I can get from analyzing those concepts is that there are some number or other there exists a number which is the correct answer and so can't actually thinks that mathematics is an example of the synthetic a priori 7+5 if we just think of that seven plus five well we all know that is twelve but we know that because we've added this a bunch of times memorized it but in the old days you might used to have to count on your hand seven eight nine ten eleven twelve you actually do the arithmetic and then you find out the answer ah the answer is 12 and now you know forever and for always that's seven plus five equals 12 so it is something which is necessary and universal but notice that it wasn't something that we got analytically we didn't get it for just by analyzing the concepts of 7 + & 5 we can have fully mastered what 7 is of course I know what 7 is it's the prime number that comes after 6 and before 8 and of course I know what 5 is it's the prime number which comes after 4 and before 6 and I know what + is it means that you add those two together I know what addition is I know what equals means you need to objects that are identical have all the same characteristics etc etc but yet even fully mastering those concepts before I did any addition whatsoever I couldn't know what the answer was so I learned something new about the subject here 7 plus 5 consider that subject term and as a sentence I learn something new about that by doing the addition but yeah at the same time I know that whatever answer I get has to be that answer every time so I can know a priori that whatever answer in fact I arrived at is a necessary and universally true answer that always will be 12 when I had 7 + 5 and I don't need to sit around and do it a bunch of times the may sure of that so it does add to my experience excuse me it does add to my knowledge it tells me something new so it's a synthetic judgement but at the same time it's an 'a priori judgement the justification of mathematics is not something based on experience even though in this particular case doing the math actually taught me something new about these numbers namely that when they're added they're equal to 12 so now of course you should probably see where this is going all of the concepts which you saw were problematic Conte is going to argue those ones fall in the synthetic are priori so cause and effect we can't know that it's necessary well that's it we can that's the fact that it's necessary is something we can know that synthetic and not priori the existence of the self as a permanent unchanging thing synthetic a priori the existence of an unobserved world that continues to exist when we're not looking at it synthetic a priori so everything that human that we couldn't know cons going to argue we can in fact come to know those things but it is only because we are developing this category of synthetic our priori truths so just to sum that up cons answered a Hume is his theory of the synthetic is his theory of synthetic a priori knowledge so let's just take an example to put all of this together take for instance the sentence fire causes pain Hume says you can't know that that's necessary it may have caused pain in you many times in the past every time you put your hand in the fire in the past you've had a certain experience of pain but of course that doesn't mean that tomorrow when you put your hand in the fire that that will cause pain for all you know that it will just cease to be that way because there's nothing necessary about it may just be accidentally for all this time that's the way that is been so this is certainly synthetic right you can analyze the concept of fire and you'll never get the concept of producing pain in us you only get that when you've actually put your hand on some or into a fire so you learn something new about fire when you feel what it's like to be burned but at the same time we can know a priori that whatever experienced fire produces in us is the one that it must always produce so that if you put your hand into the fire even before you do that you can tell ah whatever is going to happen is the necessary consequence of this event and you don't learn that from putting your hand into the fire you learn that in the same way you learn that space was necessary by thinking about the conditions that make your experience possible so if there was no necessary connection between these events the kind of experience that we have would be radically very different it wouldn't be this nice orderly regular law governed kind of experience we have in fact it would expect it to be just random not connected more like dream experience so what's our priori is that you can tell by the structure of our experience that whatever happens is going to happen again the same way the next time you do the thing in the same way so if you put your hand and you don't wear this thing and the temperature is X and the pain is a certain level and you recreate that exactly then you're going to get exactly the same result that's the thing that you know by examining your experience you can tell by the way the experiences are structured when you have dream experiences that you know you put your hand at one time it tickles you fly to the next place your grandma is there but doesn't look like your grandma everything's random disconnected nothing makes sense but in our normal waking lives we have this reliable predictable structured world that we interact with and the only way that that could be possible Conn's argues is if there were some necessary connection between these events the cause and the effect now of course you don't know what effect is going to follow from what cause a priori that's why you learn something new when you stick your hand in the fire yeah that's what fire causes but you know that once you've figured out what the effect is that that thing is something which is necessary and universal so all we've been doing though is talking about the structure of our experience and that leads us to a discussion of the phenomena and Numan a distinction and con's general view of transcendental idealism which we'll start in the next lecture

Channel: Richard Brown

Views: 121,009

Rating: 4.8434443 out of 5

Keywords: Immanuel Kant, hume, David Hume, a priori, analytic, synthetic

Id: NepDL1h1BS4

Length: 51min 20sec (3080 seconds)

Published: Tue Nov 29 2011