Cogito Ergo Sum

hello there are a few sentences in the history philosophy that had become as famous as their authors the unexamined life is not worth living said Socrates in the fifth century BC man is born free wrote Rousseau two millennia later but everywhere he is in change Pythia still is Nietzsche statement God is dead but perhaps the best-known saying in the history of philosophy is one usually quoted in Latin cogito ergo sum I think therefore I am this statement first appeared in 1637 in a work by the French philosopher Rene Descartes despite its simplicity it's the starting point for an entire system of thought today Descartes cogito argument is commonly regarded as one of the foundations of modern philosophy but what does this apparently unassuming sentence mean and why does it still prove a criticism and comment almost 400 years after it was written with me to discuss Descartes in this statement cogito ergo sum ah Susan James professor of philosophy Birkbeck College University of London John Cottingham professor emeritus of philosophy at the University of Reading and professorial research fellow at Heythrop College University of London and Stephen Mull hall professor of philosophy at the University of Oxford Susan James we've called this program cogito ergo sum but that's not how it started could you tell us what he dare God actually did right and what do you think it means well Descartes first used this phrase in passing in the work that he published in 1637 called the discourse on method a rightly conducting ones reason and seeking the truth in the sciences that was a work he wrote in French and there he wrote Japan doctors three that was translated into Latin as cogito ergo sum I think therefore I am so this is the origin of this phrase and there I think that they cast presents it as what he calls the first principle of philosophy the first metaphysical principle of philosophy later on in a work that he publishes in 1641 and meditations he then begins to spell out the argument that he's summarizing there that's I guess what we'll be discussing could you give us some idea of his background typically as education Descartes was born in tool in France and he went to a sort of grand school the Jesuit college of la flesche where a college which was reputed for providing very sound and solid education and there they cut studied grammar Latin and Greek and rhetoric mainly studying speeches of classical authors he studied mathematics and he studied philosophy he seems to have been a pretty good student and after he'd finished school he went to study law at the university of poitiers briefly and because in spite of his father's wishes that he should become a lawyer he went off to be a soldier and in Holland where he joined an army he came into contact with famous mathematician bacon and began to produce really original and creative work in geometry and algebra really solid runs of disease in his early twenties that's right and this is the beginning I think of Descartes intellectual project it's his fascination with the sort of clear method that he develops for solving mathematical problems that first of all in trances him as it were and that he then gradually turns into a more ambitious program for developing an account of the whole of the sciences as it were and understand explanatory systems that will explain the whole of nature it helps been described as fragile and then this severe Jesuit school he was allowed to stay in bed until 10 o'clock reading enormous number of books while the others had to get up goodness knows probably 3 o'clock in the morning whatever it was and yet he joined the army that seems to be rather strange it does need to be rather strange and it's not clear to me really why dicussed was so keen to join the army except that it was a way to travel and he used this as joining one army after another as a means to travel and his health was frail it seems quite likely that after he left school he had some sort of breakdown and highly vivid mental episodes are a very important part of his intellectual career John and John Cunningham what was the intellectual environment in which we grew up outside the school he had a rigorous education by the sound of it he covered everything that that the best educated young boys covered in those days in that part of Europe what was around him what was the context well the the dominant system which he would have imbibed was scholasticism which had really been going for several centuries this was a kind of fusion of the ideas of Aristotle was based on Aristotelian principles worked and elaborated so as to be consistent with the Bible and with Christian doctrine and it had various features perhaps one of the most important was that each subject was innocent separate it had its own methods and standards of precision as Aristotle himself originally said it was also qualitative that's to say things were explained things behaved the way they did because of certain real qualities they possessed for example things fell to the ground because of the quality of gravitas or heaviness now Descartes though he imbibed this system had the thought susan has mentioned his early mathematical work had the thought that actually that wasn't really very valuable as an explanation that instead you ought to look for quantitative explanations things behave the way they did because of their size and shape and motion so he started to react against the qualitative views of the Scholastic's and then also skill the scholastic system was largely purposive things were explained as moving towards a goal or purpose and again they can't reacted against this and thought instead that we should search for mechanical explanations at that time when he was a youth we had Copernicus and the heliocentric notion of the known universes were and Galileo doing his experience was he excited by these men and what they were doing very much so when he was still a schoolboy at la flesche Galileo's discoveries of the moons of Jupiter were published and that really was the first clear experimental confirmation that the earth was not the center of the of the universe as had previously been thought it was the first confirmation of the Copernican view which was which was about an a few decades before Descartes was born so it was a time of of change how many evidences to how he reacted when he read about that and what he did as a consequence of that well there was a poem performed at the school to celebrate this great new discovery and it's possible that Descartes himself may have been involved in the recitation of this poem though he had in 1619 when he was 23 he had three powerful dreams which seemed to been very important to him and very important in the formation of the way he regarded the way the world worked could you tell us about them and why what importance he drew from them yes he spent this was in November 16 19 when he was travelling as a gentleman soldier because was been mentioned in psyche he was in southern Germany and spent the whole day shut up in a stove heated room up well as he describes it in the discourse and he had three very vivid dreams the first one involved a very strong wind hurricane which pushed him around and frightened him severely he took refuge in a chapel and met someone who presented him with a fruit which he thought was a melon from a foreign country then the second dream was very quick a big bang of thunderclap and sparks and then the third dream which the most complicated there was a series of books first there was a Latin poem which begins with the line what what part in life shall I follow and then a motto of Pythagoras appeared the Greek geometer and then finally an encyclopedia and unfinished encyclopedia which he took to represent all the sciences connected together Sieben ma home what did he draw from these dreams and from his previous education it's not so much a turning point but a point had come in marked well I think one of the things that he drew and Susan mentioned earlier was the idea of the essential unity or continuity of human knowledge I mean one image that he uses famously in certain context is that of as it were a tree the tree of human knowledge with metaphysics first philosophy as the roots physics as the trunk and all the other sciences as the branches so on the one hand he seems to think that there is a fundamental unity in the whole system of human knowledge and so it must be possible in principle to articulate those various bodies of knowledge as forming part of a fundamental unity and yet there is a certain kind of hierarchy built into that image physics gets a certain kind of priority in relation to the other Natural Sciences and in turn metaphysics first philosophy has a certain priority over physics so what Descartes is committing himself to and perhaps this is what the image of the encyclopedia in the third dream was interpreted by humans as meaning he was interested in developing that project of a certain kind of unity of human knowledge but I think another aspect of the context that John was sketching in was also fundamental to his sense of how to go about developing that project if one thinks about philosophy or metaphysics is the kind of root of the whole enterprise that on which everything else has to be built then one needs some way of establishing only foundational genuinely reliable knowledge and the reliability of that knowledge can then be transmitted through the rest of the edifice if you like and the method the descartes uses as we'll talk about in more detail is that of skepticism I kind of methodical doubt and I think one of the reasons that was such a fundamental idea in the context of the time is one of the implications of the new modern science Natural Sciences as it was being developed this was not just a kind of radical break with our state alien ways of understanding nature where the quantitative became primary as opposed to the qualitative but it was also one which revealed and was certainly beginning to reveal to those who understood what was going on at the cutting edge as it were the the kind of vision of the world and one's place in it that is delivered to us naturally through the senses is fundamentally unreliable can you and take us to the book honesty and model in 1960 3070 published work known as the discourse on the method what would is this method and is this a life project is embarking on well it's certainly a conception of method that he Cleaves to throughout his intellectual career but in fact if one looks at the rules that are supposed to have encapsulate or crystallized the method they're not on the face of it hugely exciting there are four of them and three of them have to do with the principle such as the following that one should start one should break down the problems or the areas that one's trying to study into the simplest possible parts that one should build from the simple to the complex and that one should try to make sure that the chain of reasoning that goes from the simple to the complex is as exhaustive and comprehensive as possible all of that doesn't sound terribly exciting and certainly from our perspective the first principle is the one that turns out to be much more fruitful and radical than it might look in according to the first rule of this method Descartes says that one should only rely upon that which one clearly and distinctly perceives to be true and that turns out to be the core of the method that gets much more systematically articulated in the meditations Susan James it's also the first time here that he uses when became known as a cogito argument what does he mean by it well the cogito argument is something that the cutter takes over and adapts from Augustine so it's something that most of his contemporaries are quite familiar with and in its simplest form it's the idea that when you're thinking something when you're doubting something you know that you're doubting it now in the discourse which is the text that Stephen was talking about Jacob doesn't elaborate on this idea at all it's only later in the context of the meditations that he explains that what use he's going to make of this claim and that's in the context of the so called radical doubt that he develops from the first part of the meditations so you think it's almost incidental in this in this work the first word before you get the meditation I don't think it's exactly incidental I think it's offered he says that he's offering just a few metaphysical conclusions in this work to give his readers the idea that the method that he is developing there can be used and applied to first philosophy to metaphysics and I think one of the reasons it's so briefly sketched is that the discourse on method was presented originally as an introduction to three other as it were essays or texts which were about optics meteorology and geometry so as it were there's a part of the discourse on method which tells you about the first philosophy the roots of the tree if you like but it also sketches in his conception of physics and then it sketches in various implications about conception for other Natural Sciences like biology and zoology so what you get in the discourse is a certain kind of sketch of the whole of the tree whereas what happens in the meditations is that he has the room to spand upon his conception of the roots its last night how they Bank his philosophy up on so much science and was so quickly got to the number of things John Katya Mia let's develop the idea develop in a work which Susan referred to the meditations and what does he do what does he sit hard to do in that book yes if to find something stable and secure you had to demolish the whole lot and start again right from the foundations that's what he says in the opening of the first meditation that's six meditations one for each day of the week perhaps modeled a bit on the spiritual exercises of the Jesuits who brought him up and it starts with this these waves of data you push that to the limit to see if anything survives so he starts by doubting the senses our basic source of knowledge even five senses they can sometimes deceive us and we shouldn't trust what's sometimes deceived us can you give us some specific example well he L swear he mentions the the stick in water it looks bent but really it's straight well being water it's meant I mean brother exactly so yes another example he gives is the Sun and the moon they look roughly the same size but actually of course the Sun is unduly bigger so if you rely on critically uncritically on vision you can be led astray but then he says what wait a minute Here I am sitting by the fire in my winter dressing gap surely that's though certain that I couldn't be wrong but then he reasons no because sometimes I've had very vivid dreams and thought that something like this was going on only to find I was sleep in bed and then he broadened the doubt to think well maybe the whole of life might be a dream maybe all the whole external world all the images are just beamed into my mind by a malicious demon bent on deceiving me this is the extremity of that but then he comes out of that into certainty because he reasons even if I'm being deceived even if I'm doubting I must still be here in some sense to do the doubting so I'm I at least must exist so as you praise it in the meditations some exists oh I am I exist that is certain as long as I'm thinking it or putting it forward in my mind 200 develop that ISM hound this cogito ergo sum sum exists actually saves him on riding through the dance well it's you know as John says he's going down down down down and it looks as though the whole project is really about to band her on the rocks if he's going to rescue himself he's got to find something that isn't doubtful and the cogito is meant to serve this purpose but it's a very very small Archimedean point as it were from which to move the world because as Descartes points out what he can be sure of it's only that as he's having a thought he knows that he's having it as I'm remembering that I was walking down the street I know that I'm having this thought of remembering myself walking down the street of course I don't know whether it's true that I was walking down the street or as I'm doubting whether my hands are in front of me I am aware of myself having that doubt and I'm thinking that thought so as long as I'm thinking some thought or other then I know that I exist but it seems that at this stage all I know about myself at the most is that I'm this kind of succession of momentary sorts yes I mean there's nothing certain about my thinking I could stop thinking anytime I could stop existing at any time but what is certain is that as long as I am actually engaged in this reflection I must exist nothing can make me not exist as long as I'm thinking so it's a very momentary tiny flickering candle of certainty which could go out at any minute and I think that's why the question of the function of the ergo in the cogito ergo sum formulation is so fascinating and so hard to pin down because what's kind of coming out already is that there's a certain kind of performative aspect to the argument if it is an argument that's being presented to us the force of the conclusion is only going to as it were have an impact on us insofar as we are actually engaged in the process of reflection that delivers that conclusion and that kind of connects with a bigger issue which is that as arguments go cogito ergo soon looks like a very peculiar kind of argument or certainly would have at the time I mean the kind of canonical example that philosophers always off offer of argument structure is involve Socrates as you might expect you know all men are mortal Socrates is man therefore Socrates is mortal you only get to the conclusion because you have two other claims two premises from which the conclusion follows so when someone tells you cogito ergo sum you naturally start looking for what the premises might be and usually at least in the form of a syllogistic argument one premise isn't enough and you can't just have Kolkata there must be some more general major premise in the background one might think such that everything that thinks exists then if you can say I'm thinking it would follow that you exist but that can't be the right way of understanding the argument because it would involve Descartes assuming the truth of the general premise when he's precisely got himself right down to the roots at which the force of the evil demon hypothesis is supposed to prevent you from assuming the general truth of any you're going to Susan first of all and in fact Descartes says doesn't he indan replies to his objectors but this isn't really the way he wants one to take the argument he says of course you can present this stuff in a kind of logical form once you know it but that's not the order of discovery the order of discovery is that you perceive with a simple intuition of the mind I am I exist and that is how you get started this means I mean I think he was aware that all sorts of elaborate syllogisms and arguments could be rolled out and sort of things he'd learnt at school but this is different this is something each person has to do for themselves in fact he says in an introduction I don't want to have anything to do with anyone who's not prepared to follow me along this part and meditate for themselves so medet the title of meditations there's no accident it's something each each person has to do for themselves how important is proof of the existence of God to Descartes argument well he's got to get out of this tiny flickering candle of subjective certainty to something bigger something more systematic to nollet or whole system of knowledge he can't do it just on his own and the way in which God under pines' I think is this that once he's aware of himself as existing he's immediately aware of his imperfection of himself as finite they're many things he doesn't know many things he can't do and yet he has a sense of the infinite of something infinitely greater than himself so he has the idea against the sense of himself as finite he has the idea of this infinite being and this idea he reasons couldn't have been created by him from his own resources and therefore must have been put in his mind by God as he puts it like like the mark of the craftsman stamped on his work and trademark and once God's in the picture then we get we get something good and benevolent which and he can then reason that his mind is a reliable instrument as he puts it in an interview a reliable mind was God's gift to me and once he knows he's got a reliable mind then he can get going and build his new system of science but does he believe there's a god a reason his way to God Susan well probably both I think I mean it seems to me that what he gives us proofs of God are not tremendously convincing as theological proofs and indeed none of his contemporaries seemed to be content with them it's almost as though Descartes is sort of indulge well he's engaged on a kind of exploration of his ideas and the process of meditation is one of becoming more clear about ideas that they cough takes it actually are already innate in your mind they're already there and so what you're doing is uncovering them or finding them and so he's sort of finding his idea of God can I stay with you for a moment his arguments raise the question of the relationship between the mind and the body can you tell us what that means for Descartes well we've seen that the cogito shows you that you're capable of thinking and also they cut argued capable of a variety of kinds of thinking you can have the Lycians and perceptions and memories and so on a thing that thinks is what you are at this point in the story and a thing that thinks they're custard is what we call a mind so we're beginning to learn something about the mind and as Steven said we have this kind of clear and distinct idea of this mind as something that exists and we can now begin to explore it so that license is jacob to sort of look into his mind as it were and see what other ideas he finds hanging around in it and one of the ideas he finds is God as John just explained but another of the ideas he finds is his idea of physical bodies and so he now asks him so all right well what kind of really clear an indubitable idea do i have can i uncover of a body and he says well the normal thing would be to say that as well a body is something that you know through its sensory properties but I'm putting a letter side because I I've got all that under doubt what I do know about a body for sure is that in order to be a body it must have certain essential properties which they cut cause extension or extended nosaka speaking it must have shape and size so it's got these quantifiable properties of shape and size so they cut things now he knows clearly and distinctly water bodies so he's got to clear and distinct ideas one of his mind as something fundamentally thinking the other of his body as fundamentally extended and he's now in a position to see that he is also he argues that these are distinct that as it were there's nothing in his idea of a mind which depends on his idea of a body and there's nothing in his idea of body which is where depends on the existence of the mind and um through the argument of the meditations Descartes arrives at the conclusion that these are distinct substances distinct kinds of things each of them absolutely fundamental and so now he's done something quite dramatic really which is that he's generated a conception of body a quantifiable conception of body that can be the basis of physical science and the quite separate idea of a mind which is just something that thinks and you have to remember that this is against a background of an Aristotelian notion of a mind or so which has all sorts of capacities other than thinking did this turn in this argument erm john cutting helped his larger philosophical project was it the key well certainly the idea of extension that Suz mentioned was was crucial extension let's just say length breadth like the three dimensions this forms the basis for geometry and therefore in de cartes way of thinking for physics so physics really becomes a comprehensive system which will include all the particles in the universe not just planets stars earth stones rocks trees plants the whole lot can all be described he thinks in terms of geometrical properties of extension except consciousness thought so although he's a great unifier he has this wonderful vision of a geometrical unified system of physics the world of thought and consciousness is left on one side is not able to be quantified and measured and that's the that's the project he leaves us with in a way kind of unfinished project everything can be subsumed under geometrical physics except for thought and consciousness even it seems to be slightly odd very much on outside and very much a sort of beginner that having in his mathematics got down to particles and said it does come down this particle and that each which is entirely it's a different thing altogether the mind so it is although it's inside the body and helps the body to function and maybe function as a body it is distinct thing work well here some of this contemporaries eager to challenge him on that from the beginning what were the arguments against was that one of the arguments against well I suppose in the context of the meditations it's very clear that this sense of a fundamental essential distinctness between mind and body comes out of the application of the method of sceptical doubt because if as it were the minds manifestation of itself as thinking is immune to that doubt but it is possible for the meditator to doubt the existence of everything external to the present moment of consciousness then it looks as if you can conceive of yourself as existing in an entirely non material way in a conception of the world in which there is no material body but is yours or you so that in a sense is a radical consequence of the application of his method but in another sense there's a way in which this sense of mind and body in its essential distinctness fits into broader cultural context particularly theological ones because what it suggests is that if the mind is essentially immaterial then a belief in the immortality of the soul is entirely consistent with the basic principles of first philosophy matter is the kind of thing that decays and decomposes because it's extended it's divisible something which is essentially non material is indivisible so what you get is a conception of the mind which is entirely consonant with the conception of the soul as being of the essence of the human individual and to that extent it feeds into the kind of continuing affection and loyalty that Descartes always showed to the church but there's a Cartesian Circle I'm with Antoine Garner's objections one day a hundred day but worried about the Cartesian Circle goes back to this question about the function of God in the system as they got presented in the meditations and John was explaining a little earlier that part of what's going on there is that God gives us a reason to treat not just our senses but our reason perceptions of rationality as generally reliable so the way de Kock presents the situation is that one has the certainty of the cogito one perceives the truth of the cogito by means of clear instinct perception the exercise of reason and because one knows that God exists God is the guarantor of the general liability of clear and distinct perceptions so God shows us that we can trust in these perceptions of the mind the objection the worry that's encompassed in the idea of there being something circular here is on what basis do we believe in God's existence if not the fact that we clearly and distinctly perceive the truth of the arguments Descartes offers for that belief but it's God who's supposed to underwrite the validity of that general criterion for truthfulness another way of putting this in addition to the cogito which we've talked about there's an earlier formulation which comes in a book of his called the rules for the direction of the mind which is some go day obsessed I am therefore God exists and the circle arises because it Descartes clearly wants to move from himself to God but to reason from himself to God he needs to trust the reasoning process of some sort and how is he going to do that unless as it were he knows God is there in the first place guaranteeing the reliability of his reasoning so it looks as if the whole thing is a vicious circle can we see how it was received Susan James talking about how for example Hobbes received this argument and Spinoza if you could give us some indication in the dynamism well Hobbes is one of the people who is invited to write objections to the medications and they cut replies to them Hobbes is a materialist and picks take us up on the cogito argument in particular and and raises the question of what this is that's doing the thinking Descartes says it's a mind but Hobbes says you say it's in mind but you know how can you be sure that as well that's all it is maybe it's also a body and actually Hobbes Hobbes seems to think that it must be a body because only bodies can be as weather subjects but a capable of having thoughts predicated of them dick hot points are quite reasonably that Hobbes is sort of begging the question there but nonetheless there is a problem or but I think many of Descartes contemporaries are very interested in which is so sort of water exactly this cogito argument establishes about who this eye is on the one hand is it a body on the other hand is it even a mind is it anything so as we're unified is it just this kind of flickering in and out of you know sequence of thoughts that John mentioned before is it even something that you can attach first person to maybe he should say we are thinking this is what I need you said it is thinking it is thinking exactly or even a new thinking is going on you know as it were sort of subject to this thinking so there are a lot of problems here about this and and d-cups contemporaries of you know pretty acute lot to bear on to them to move on from this contemporaries can you give us some idea of other reactions John I've got names only Heidegger meetcha and so as the centuries rolled through analyst this remark appears and this philosophy of his was taken seriously even when it was dismissed seriously a preserve it seems to be in a fairly foundational notion yes well as the centuries grow on there's a lot of emphasis on subjectivity that the movement we know is existentialism there's a lot of stress on the individual awareness of the subject and the idea that the subjects gotta somehow construct reality from from him or herself and that in a way is Descartes starting further in the sense they're inheriting that Cartesian starting point of the individual existing self and starting philosophy from there but the difference I think is that when you get on to Nietzsche and such - you mentioned you've got Descartes but without God you've got the whole thing depending on just the individual thinker meditating and wondering what's going on whereas with Descartes you've got this radical subjective reflection but against the background of a first even mentioned of a firm belief traditional belief in the source the infinite source of his being God so the moderns are very different I think although they see Descartes is there ancestor Sartre is a particularly good example of that I think because on the one hand he's wholly explicit about his indebtedness to Descartes he thinks that any project of philosophical system building has to begin with the truth of subjectivity but he offers what seemed like a really minor tweak to the validity of the cogito and the conception of the mind that Descartes generates from it that just utterly explodes the Cartesian system as as Descartes would have would have understood it because Sartre kind of points out two things first of all he says that Descartes argument trades on the assumption that whenever one is in a state of consciousness one is also and simultaneously explicitly aware of being in that state and Sartre says that that in fact isn't always the case what is true what is necessary true about the mind is that one is capable of reflecting on the state one is in but it's not true that one is always explicitly aware of that state simultaneous with being in that state so that creates a certain kind of problem which Sartre summarizes by saying the cogito is not reflective but pre reflective being capable reflecting on oneself is essential to subjectivity but it's not true that it's always explicit and that means that Descartes can't assume that whatever state of consciousness one is in when it's simultaneously necessarily aware of being in that state and without that assumption the cogito arguments however one causes it is not going to work in the way that they can't thought it did the other problem that Sartre raises is that when one does activate that reflective capacity and does take one's state of consciousness as an object of reflection then one is no longer in that state of consciousness suppose I'm to use one side as examples in a state of warfare in which cigarettes are rationed and I'm desperately counting the cigarettes in my case to see when I've got enough left to last to the end of the month well when I'm focused entirely on that task then there's no explicit reflective awareness of what I'm doing on my part but if someone comes along the street and asks me what I'm doing I can perfectly well immediately tell them and the moment I move into that state of reflecting on what I was doing then the counting the cigarettes I'm no longer counting them I'm now in a different state of consciousness which has as its object not the cigarettes in the case but myself in the past counting those cigarettes so the move from pre reflection to reflection is also a change in the state of consciousness and that means that time intervenes between being in that state of awareness and being reflectively aware of being in that state so the subject enters time if I'm thinking just to add in fairness to Descartes I think we've been talking today about very transparent thoughts or conscious acts like cogito ergo sum but in his later work Descartes acknowledged that there's a lot of other stuff notably passions and emotions love hate fear which are much more complicated and where we don't have such immediate transparent awareness of all of all the implications of what's going on inside us I'm a Susan is Descartes still someone that contemporary philosophers take seriously work with enormous Lee I think I think the deckhouse keeps on resurfacing in a fascinating way and sort of kind of a chameleon one of these great chameleons that's constantly putting on new dresses I suppose that the cogito continues to be sort of at the root of contemporary work on the nature of self-consciousness and de cast also has recently become I suppose much more a figure studied for his work on the passions and the relations and these kind of more obscure relationships between mind and body that John just alluded to well thank you very much Susan James even Mulhall john Cottingham and next week we'll be talking about the origins of Sharia Islamic law and thank you for listening

Channel: Philosophy Overdose

Views: 11,565

Rating: 4.8636365 out of 5

Keywords: Philosophy, History of Philosophy, Descartes, Cogito, Cogito Ergo Sum, Cartesian, Skepticism, Scepticism, Discourse on the Method, First Philosophy, Epistemology, Philosophy of Mind, René Descartes, Foundationalism, Certainty, Philosophical Skepticism, Dualism, Western Philosophy, Rationalism, Cartesian Doubt, Solipsism, Theory of Knowledge, Philosophical Realism, Mind-Body, Consciousness, Subjectivity, Subject-Object, Self-Consciousness

Id: YMoPUwNK0fQ

Length: 41min 53sec (2513 seconds)

Published: Tue Jul 04 2017