Dr. Darren Staloff, Descartes Epistemology

[Music] so [Music] with the philosopher rene descartes we enter an entirely new epoch in the history of philosophy i'd mentioned previously how the pre-socratic set a problematic as it were for the ancient world for the greeks and after them the great christian thinkers how they set up issues and problems descartes does that for the modern period he is indeed the father of modern philosophy we'll find that in modern philosophy argument becomes far less dialectical and by dialectical i mean intuitive commonsensical and far more formal so a far greater sense of logical precision of argumentative accuracy and in large part that's the result of the scientific revolution and descartes was a important part of the scientific revolution those of you i'm sure who've done any higher mathematics have studied his work analytic geometry is in fact the child of descartes you studied the cartesian coordinate system it's the same fellow he also read the works of galileo copernicus he knew of all the cosmological speculation of his time in other words we're looking at a figure who was one of the fathers of modern science and modern philosophy and the key to his modern philosophy is the temp the attempt to take that same scientific precision accuracy sensibility and use it to approach metaphysical problems and philosophical problems now i want to pause for a minute to talk about modernity itself and philosophy why or what rather do we mean when we say philosophy has been made modern a lot of different senses but the most obvious historical sense is it comes on the heel of the renaissance what renaissance means is rebirth and what it was was the rebirth of classical learning of the greats that you've previously heard of plato aristotle socrates what separates modern philosophy then from the epic that proceeds with the renaissance is the sense that we no longer have to look over our shoulders at the greats of the past that we have the analytic and cognitive tools to go beyond them to create new philosophies to create a new understanding of the universe far superior to theirs and i can't stress enough how much this is a reflection of a new growing sense of confidence within the west particularly within the western speculative tradition that no longer need we be live in the shadow of aristotle the shadow of augustine the shadow of plato we have new things to say that may be more important more accurate and more true than anything they had to say before so that is the sense in which descartes is the father of modern philosophy he specifically refused to footnote anything in his text to plato aristotle any figure we've looked at he refused because he said if you do that what is the nature of your argument you're arguing from authority right you're saying well i believe x because well plato said x and plato's a real smart guy therefore x must be the case the scientific conception of philosophy is that whatever i believe i should be able to scientifically and logically prove authority has no place in such disputation and that is the project that descartes attempts to pursue but he goes beyond that in fact he argues that we have to go beyond merely probabilistic arguments but if we're to have a truly scientific philosophy it must be absolutely certain it must be built on the most firm foundations possible it must in other words be completely proven and indisputable that i'm i would argue is a rather tough bill to fill as it were that's a tough task to to try and complete and i must confess descartes did not entirely do that one of the fundamental problems of philosophy is ethics and descartes never quite got around to it but he made an excellent start a start which has influenced every thinker since in so many ways at least for the next three centuries philosophers are attempting to deal with the issues descartes has laid down and they're trying to do them in terms of the way descartes framed questions okay then the question becomes how do we build philosophy on a completely certain foundation and that raises the question of method we must begin with a method which can only produce truth which can only produce logically correct arguments which can only produce complete persuasion and that of course is the famous cartesian method i'm going to look at that method i'm going to look at the way he uses it once he's established it to create his metaphysic a metaphysic which is most commonly referred to as mind body dualism now the method comprised four different components or steps the first step is what he called systematic doubt we must reject as false provisionally at least every single proposition which is only probable no matter how obvious it may seem if we cannot prove it if it's not entirely certain and indubitable and we if we can't prove it's indubitable we must provisionally at least reject it as false so we begin only with that which can absolutely and certainly be claimed to be true and that is the philosophical starting point given that when you find something which you know absolutely and it comprises let's say a problem or issue you have to as he says break it down chop it up what we call in fact what ancient greeks called as well analysis right analysis is simply that you take a large scale problem and you break it down into its smallest component parts so we begin with systematic doubt and then move forward to analysis once you have analysis then you enter the process of rational reconstruction a problem has been broken down into its bits now it must be reconstructed into its totality into its unity into its whole and that must be done we call that process synthesis by the way that must be done logically through proof and in fact to ensure that such proofs are logical descartes insists that you don't do them intuitive intuitively don't do them in your mind don't talk about them write them down write them down just as you would a proof in euclidean geometry and again i we must remember descartes is a pioneer in modern analytic geometry that is his model of rational inquiry and what we have in geometry i think we can fairly claim is absolute certainty we must take that method and apply it to metaphysical issues so then with those four steps systematic doubt analysis synthesis and careful recapitulation of our arguments we have the cartesian method well let's then begin with this systematic doubt now this is a difficult concept for most people who have not studied philosophy to make much sense of i mean we all can think of things we can doubt right in a very ordinary sort of sense i for one have never been to japan i've seen pictures of it i've heard people talk about it but i've never been there in an obvious sense i can doubt the existence of japan i mean everybody in the world may be part of some huge conspiracy that endeavors to convince me that there's really this place on the other side of the world when in fact there's not that's possible similarly i can doubt the existence of neptune i've never seen it i've seen maps but people could be lying to me stranger things have been known to happen okay that's an intuitive sense of doubt but descartes says that's not enough there's more than that that you can doubt right you can doubt for example that you had for breakfast what you had for breakfast yesterday how so well sometimes you dream don't you maybe you dreamed you had breakfast how can you tell the difference can you prove that you actually had that breakfast maybe and maybe not what do you only have as certainty what is the only thing which you're actually aware of and here is descartes great innovation the only thing you're really aware of is as it were a show between your ears right consider it all of what you immediately apprehend are cognitive states or representations then the question becomes representations of what okay he then goes in to a famous argument that we can even doubt our own material physical existence and he employs a method which is quite logical and sensible um what i'm going to offer you is a sort of modern version of it it's logically identical but it's simply jazzed up in a form which at least for for college students is far more intuitive and obvious to them descartes makes reference to an evil genie i'm going to talk about a mad scientist big heart says in fact imagine if you will that there exists this crazy mad evil scientist he's brilliant little demented but brilliant he's brilliant in two particular fields one neurology he has mapped out all of your neural states all of your neurochemicals simulations in your brain the stimulation of your c fibers he knows exactly which ones correspond to each of your sensual apprehensions each of the moments in that show between your ears that you're aware of not only is he able to do that he's also developed a super smart computer he's a great cybernetic expert and the super smart computer can instantaneously collate each of your neural states each of perhaps your drives that are going on in your brain with the correct physical analog that you should experience in a normal day or in any normal setting but there's more to it than that he's also found a way of taking brains keeping them alive and putting them in a large vat of nutrient solution that keeps them alive sustains them so he's got this huge vat full of brains in a nutrient solution and what he does is and this is dastardly as can be he connects those brains all the neural synapses to that super smart computer and he feeds them datum in other words he he said he tells that super smart computer to feed to the brain the sense datum that it's actually in a body and not in a vat so it has all the sense status of say sitting in a chair and it's actually sent the neural stimulation of the feeling of the texture of a hard chair under your legs the feeling of a hard back behind you the feeling of of a dark black floor underneath your feet but he's even more insidious than that he tempts you with horrible images in other words he actually makes you think you're sitting in a lecture room and that there's some crazy guy up on a podium walking back and forth telling you that you're a brain in a vat in short the question descartes asks is to each of you how do you know you're really in this room how do you know i'm really talking to you how do you know you're not just a brain in a vat being sent electrical stimulations into your neural structure which simulate all the physical analogs of a professor walking back and forth on a podium talking about brains in a vat think about that for a minute that's a rather difficult problem that incidentally is the problem of modern skepticism how do we know we're really here we could be dreaming we could be brains in a vat okay well descartes thinks for a long time how am i going to think myself out of this bat i don't want to be in a vat how do i even know i exist and then he comes up with an answer he says you know i doubt my physical existence i doubt your physical existence who knows maybe i'm the only brain into that maybe i'm not even a brain maybe there's not even any bad but you know there's one thing that occurs to him as i doubt i doubt there must be something having the cognitive state of doubt therefore there is something that exists a doubting subject and we call that doubting subject i so descartes can therefore state categorically cogito er gosun i think therefore i am it's a logical necessity it is impossible to contradict that so one thing we can each and all be certain of absolutely our priori and logically that you exist as long as you think what about everyone else perhaps you're the only thinking thing in the universe well he says let's step back for a minute we have one sentence which we know absolutely is true i think therefore i am well since we have a true sentence let's examine it carefully and see what is it about that sentence that marks it off as true and he thinks about it and he says it's quite obvious i intuitively apprehended in a clear and distinct fashion i have many mental representations lots of things go on in that show between my ears lots of ideas pass my mind but this one is so clear and distinct so intuitively obvious that i can't reject it and we have here the birth of the cartesian epistemology an epistemology of clear and distinct ideas and again think yourself back into descartes position and it should be actually quite similar to your own position we have not moved very far beyond the cartesian problematic it's still a modern problematic when you get representations of various uh cognitive states various things going on that show between your ears how do you know which are true and which are false how do you know that when you see a let's say a hallucination or a mirage it's just that he said well in a certain sense mirages and dreams are sort of fuzzy and vague but the things which you know actually accurately represent are clear and distinct um a modern philosopher by the name of richard rorty is given a very nice metaphor for this he says what the cartesian problem is sort of like the mind is this big mirror and it mirrors everything that's going on outside of it some of the reflections of course are simply of appearance and not of reality how do we tell the difference well we're sort of in the brain or in the mind as it were looking at the mirror and some of the reflections in the mirror are clear and distinct and some of them are fuzzy the clear and distinct ones are obviously more accurate representations than the others this doctrine of the cogito not only has therefore an important epistemological basis to it it's also been an important insight for other philosophic movements uh in subsequent lectures we'll be talking about existentialism many existentialists feel that karts kogito was the very first existential doctrine now before we go any farther we have to be clear what exactly is a thinking thing or mind and he's quite clear it's not what previous philosophers have talked about don't confuse the mind with the soul in fact he has a wonderful statement where he says i'm not some subtle air infused into these members right the pre-socratic notion of the soul not a wind not a fire not a vapor not a breath nothing that i imagine to myself for i have supposed all these to be nothing what then is a mind what are its fundamental properties and these states but what then am i a thing that thinks what is that a thing that doubts understands affirms denies wills refuses and which also imagines consensus that is the modern notion of mind no one had ever expressed that before rene descartes one of the fundamental breakthroughs in western speculation so we have the certainty of our mind's existence and we know that all the clear and distinct ideas that pass in the mind are true let's now examine some of those clear and distinct ideas are there any others do you not intuitively apprehend geometrical proofs in a clear and distinct way do you not in fact intuitively apprehend logic in a clear and distinct way therefore we can know even if our bodies don't exist even if we really are just brains and that that the proofs of geometry are true and that logic is true but there's one other idea that we have that descartes finds very interesting each of us know how to use a three-letter word god each of us have a concept of god where did that come from descartes asks he says well could it come from your imagination but how so how can you imagine what you've never experienced therefore perhaps the idea of god is something imprinted on us from outside sort of the way an artist signs a painting the concept of god comes from our creator and he offers several proofs for the existence of god which he considers quite logical the most famous of which is the ontological argument it says let's just be purely analytic suspend belief for a minute in god and just talk about what the notion or concept of god includes god could be defined as a perfect being so now let's talk about what would be the properties of such a perfect being undoubtedly would be omniscient omnipotent unchanging wise you've got all those properties keep them in your mind i know he asks you the following question okay and we're talking about a perfect being with all those properties which would be more perfect if it existed or if it didn't exist if it existed obviously therefore existence is part of the very concept of god if you can have the concept of god that in itself is a logical proof that god must exist elsewise where did you have the concept he offers another proof in favor of god he says well you have an idea of god that includes perfection any idea you have must have as much reality as whatever it is that caused it have you ever experienced anything perfect only something perfect could cause the idea of perfection and what would we call something perfect three-letter word god now would it make sense for god a perfect being to be a liar no why would it deceive that's a fault of ice therefore we can say with certainty that god is no deceiver he doesn't lie to us and since we perceive a world around us there's no reason to assume that god is an evil scientist playing games with our neural structures there really is a world out there and we can know it because we know that god exists as a logical concept as an absolutely provable entity and since god is no deceiver we can then begin to trust that the an extended world exists now i want to turn to the establishment of the mind body dualism descartes says uh in accordance with in fact the logical principle of identity that two things are identical are the same if and only if they share every and all properties if there's any property they don't share therefore they're not the same thing and that's how we individuate entities in the world but he points out you can doubt the existence of your body can't you right it's possible that you're a brain in a vat but you cannot doubt the existence of your own mind right so therefore we can logically prove that your mind is not the same as your body joel follow that great mind is a completely distinct entity from body and in fact if we choose to look at it we'll see that they have very different properties descartes says what are the properties of bodies they're extended what does that mean well for us i think the best analog would be they're spacious temporal they have volume and that of course is an important breakthrough because instead of the old substantialist notion of body that it's it's an or stop or something like that he points out that what physics really talks about is the spacio temporal that's the modern way of conceiving of the physical it's that which takes up space and exists in time but is the mind extended how big is your mind i hope i have as large a mind as you do moreover all physically extended things can be divided right we could take this lectern here and cut it in half tell me what would it be like to have half a mind or a quarter mind you ever looked at a quarter of a concept how about three eighths of a notion right the point is mines are not spatial temporal they correspond to a completely distinct ontological realm they're unextended they're undetermined by material phenomena and they're indivisible we can't cut out half your mind and we can't have three quarters of an idea so we have a universe with two substances right mind and body and that i would argue is the modern worldview now as i say this i should point something out i want to point something out first of all historically this may seem like a very similar doctrine to something you've seen before right plato's ontological dualism the realm of ideas and the realm of material things and indeed at first that looks to be extremely similar where would ideas fit except for in the mind but if we return to those properties that distinguish mine for descartes we see there's a subtle difference what made up the ideas for plato were universals right we're abstract entities for descartes they're phenomenal states they're the sorts of things of which you have an immediate awareness in all of your conscious life that's the mind and again i must stress no one had ever thought of mind or created mind in that way it's a real replacement for soul having established this i think path breaking doctrine i want to suggest ways in which in fact it's kind of problematic it's a very careful logical proof but it raised issues that descartes was perhaps not aware of but which subsequent cartesians had to deal with first of all if mind and body are two completely distinct realms how can they possibly interact right minds or intentional states bodies are physically efficiently caused how does a physical thing which has nothing in common with a mental thing cause a mental state and yet we all seem to believe somehow that our mental states affect our physical being i can if i choose and will to lift my arm lift my arm how then do we explain the fact that our mental states seem to correspond to our physical emotions how does mind interact with body descartes when it was posed to him by thomas hobbs came up with unfortunately a most embarrassing doctrine he said well in the center of your brain is the is the pineal gland excuse me the pituitary gland it says well what happens is you get sensual motion and bodies which are purely atoms in the void extended things with purely mathematical properties and they send sort of electrical signals up to the pineal gland and that's where your soul is hanging out or excuse me your mind is hanging out and your pineal gland and sort of somehow rather they push against it it's very difficult to push against the non-spatial thing if you've ever tried it it's very difficult to imagine how a non-extended substance can fit in something like a pineal or pituitary gland but nonetheless that was his view subsequent to him uh other cartesians attempted to come up with far more how would we say rational explanations of the doctrine the most famous of which was called parallelism think of the universe with two distinct realms as two big clocks perfectly timed to each other by god so as each thing happens in the physical world entirely unconnected to it but exactly parallel to it things occur in your phenomenal or conscious state another view was called occasionalism very much like parallelism but when the parallels had to occurred occur god took the occasion to make sure you had the right cognitive state okay that's one sense in which it's problematic there's another sense for all of his logic and brilliance it's a completely bogus proof and i wanted to spend some time to try and show you in fact how it is bogus on purely logical grounds key is that mind is undoubtable and body is doubtable the question is what kind of a property is doubtability modern cartesian analytic philosophy has taught us in fact since descartes time but states of belief and doubt are what are called referentially opaque that is to say what we doubt and belief and believe are not things but sentences in other words i i don't doubt this lectern i doubt the sentence that this lectern exists i don't doubt this coffee cup though i may doubt the sentence that this coffee cup exists okay that's an extremely abstract argument it can very often take me at least about an hour and a half to explain it to people but i want to give you an intuitive example which is quite common in logic which can illustrate it an example of referential opacity suppose that doubtability and belief statements were not referentially opaque if that was so the following would be a completely legitimate proof take a piece of paper and write the following words tigers eat meat below that write the sentence tiger is a five letter word [Music] got those two starting to figure out what the inference is five letter words eat meat circle gets the square absolutely it's a completely logical proof so therefore we know that five letter words go around eating meat they're carnivores all right how do we show that this is a bogus proof we point out tigers here eat meat this word refers to an object in the second sentence tiger has to be quoted it doesn't refer to an object at all it refers to a string of symbols that's what we mean by referential opacity that the reference is not to the object that the word normally gestures at but rather to the string of symbols itself every time you use doubt and belief what follows should be quoted and that's indicated in normal english grammar by the word that i doubt that the body exists you can always replace replace the word that with quotations around the following words and put it before the other expression i doubt that the body exists quote the body exists end quote is doubtable that's the synonymy what does descartes do he pretends the quotation marks aren't there and goes on that's still a pretty abstract argument so i'm going to try and give it to you on a more intuitive level a common sense everyday example the one i'm going to draw from a friend of mine told me he claims to have gotten it from a philosopher named nelson goodman it's a story that goes something like this when i was a kid my dad used to own a liquor store and you know it was a decent life every friday we get together with his family his three brothers and his parents um but on tuesdays this crazy lady the local drunk would come in we'll call her crazy sally she'd come in and she'd be all disheveled and you know at loose ends and come in and say can i have a bottle of mad dog 2020 and you know my dad was a nice guy he used to give crazy sally a bottle of mad dog 20 20 on the house because she was the neighborhood drunk and she was a very nice lady in fact she was always very nice to me i could not doubt the existence of crazy sally could i she was there every tuesday like clockwork for mad dog 2020 however i did doubt the existence of my aunt sally but it turns out sally was the black sheep of the family never showed up to the family get-togethers and they kept it a secret for me they were afraid i'd be scandalized and therefore if descartes is right sally can't be my aunt but in fact she was or at least so the story goes okay so we can see that this is as it were logically a bogus proof but can we stop there and say okay it was a bogus proof don't be idea mind and body aren't distinct no i think the real point the real critical payoff is to notice something descartes is a was a brilliant thinker i don't think he was aware of this problem this disquotational issue and referential opacity is one of the really modern analytic concepts that we've developed in the last 120 years or so but i think he probably did realize that the proof may have been a little bit shaky and the question is not to say well how could he have made such a leap but rather to see what is he really trying to do he has the intuition that there's something different in him than in a piece of wood and yet it can't be the physical nature of it because they're both made of the same thing atoms right they're both extended things with magnitude and mass that's all that they are those are the primary qualities from their horizon essentially things like colors and textures but those aren't in the things themselves the things are purely physical entities as the modern physicists would argue and he's trying to prove somehow to cash that intuition in that somehow i'm different than a dog than a cat but there's something different than in me than a monkey and i think we all have that intuition it would be absurd not to the lesson to draw is how difficult it is to prove it not that it can't be proven i'm not sure it can't be proven but i am sure that descartes didn't succeed because it's a very difficult thing to prove how does one show that there is a huge gap between ourselves and physical phenomena let me be clear about descartes view of physical things he's not a teleologist he entirely rejected the aristotelian tradition it's a modern scientific conception as described tells us if i could get my organic chemistry to a more advanced level and could design right a mechanical organically designed monkey and wind it up and get it going you wouldn't be able to tell the difference between that and what you find in the environment a monkey and any animal is like a machine it has no will it has no soul it's simply matter in motion caused by instinctual reactions which are genetically programmed he didn't know about genes but he had that sort of conception a mechanistic conception of material things am i like that i mean do i get wound up before i come out here and then just pace back and forth and am i a mindless entity that just vocalizes none of us experience our life that way and so we try to cash it in in proofs so again i don't want to suggest that descartes was a dope he wasn't he was a brilliant man i don't want to suggest that mind body dualism is dopey i want to suggest that it's one of the fundamentally modern problematics the issues of somehow trying to distinguish the mind from the body what is distinct about our mental cognitive states and the world around us now i want to mention what the implications of it are descartes is trying to respond to the problem of skepticism and solacism right solipsism is the argument that how do you know you're not sin you're all certain you're there how do you know that there's anyone else there how do you know like the brain and the vat that you're not being sent images of everyone around you and that in fact you're not the only one in the entire universe kind of lonely but entirely logically plausible and that's one of the problems that descartes resolves by positing god in fact trying to prove the existence of god the other problem is skepticism how can we prove that we have knowledge and that's why he comes up with the method for certainty much to his chagrin or perhaps not to issue i don't think he was aware of it what he really did was transform the nature of skepticism what he pointed out for the first time which the greeks with their hylomorphic nations were not aware of was that all we are immediately aware of is a show between our ears is a series of purely mental representations it is as it were a veil of ideas whereas in the previous period skepticism had devolved around the senses how do i know my senses are accurate here the problem becomes how do i know my ideas accurately represent the things in the world in and of themselves and in many cases they don't i mean i have the idea of say several members of the audience as of a particular color a particular texture perhaps i went up and smelled you did a little olive factory inspection inspection perhaps a little odor certainly under these bright lights would be understandable and the point is in that case we can't be certain all i have is as it were those representations in fact descartes argues you don't really have those properties the color is simply the reflection refraction of light on my optic nerve you really don't have a color right your odor is again simply a physical analog in my sense apparatus of whatever chemical processes are occurring within you so the processes that after this other philosophers will have to deal with is how do we know our ideas accurately represent a world around us and we're going to see that there are fundamentally two different ways of approaching this problem one is the cartesian rationalistic way there must be something within ideas themselves which mark out their truth clarity and distinction what we'll see in a few lectures down the road will be that there is another tradition which emerges and attempts to deal with this problem and that's called empiricism and it says you can't examine that veil of ideas in and of itself what you have to ask is what do the senses represent how did the senses work and from that you recursively prove what must exist rather than uh in and of itself examining those representations so in conclusion then i would stress that descartes is not only the father of modern philosophy not only the father of our of our present conception of ourselves as minds mental entities but is in fact the founder of the modern problematic the modern technique the modern quest for certainty no longer will we be satisfied with really probable arguments no longer will we simply speculate about metaphysics we must now prove metaphysics with the same clarity of science and in conclusion i would point out one important characteristic of this one of the fields of philosophy at the time was called the philosophy of nature the fruits of such philosophic research in the philosophy of nature and in addition to in philosophy of man is something called galilean science newtonian science we call that science at the time it was called natural philosophy therefore what i'm arguing is that the modern scientific tradition is closely intertwined with that of philosophical speculation and it all begins in the 17th century with renee descartes

Channel: Michael Sugrue

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Keywords: Michael Sugrue, Dr. Michael Sugrue, Lecture, History, Philosophy, Western Culture, Western Intellectual Tradition, Western Literary Tradition, Author, Literature, Great Minds, Comte, Origins, Sociology

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Length: 40min 36sec (2436 seconds)

Published: Thu Mar 24 2022