Descartes on Substance

hello good afternoon welcome to introduction to philosophy again so um this week we are moving away from philosophy of religion and we will be talking about metaphysics so um before I you know go into the details I want to say a few things about what metaphysics is so um there is really one question that metaphysics is concerned with and that is the nature of reality so to study metaphysics is to be concerned with the nature of reality now in order to understand in order to get a grip on the nature of reality philosophers are usually also concerned with another related question which is what is out there um well the two questions are related because you know if you ask the common person or what is the nature of reality now he will tell you that well um there are certain things that there are you know out there in the world like tables and chairs and animals and other people know to say that in order to to say that and that is to say that is to assume that uh that reality is such that it consists of physical things in addition the common person will also tell you that um he has certain thoughts in his mind he's thinking certain thoughts he has certain feelings he sees certain things with his sense organs like his pies so when he says that he's also assuming for the most part that there are mental things that are different from physical things so so you see that there is this sort of a common sense view of what reality consists in now what philosophers are concerned to do is to ask questions about this common-sense view philosophers often send us whether this common-sense view is true and if you can stand up to philosophy course Kootenay so the history of metaphysics are is actually our history of philosophers trying to grapple with this basic question of what non reality is and what out there and maybe more some philosophers even question whether there is an out there in the first place so um so very briefly you know the as I said the history of philosophy the history of metaphysics is a history of philosophers trying to ask the question of what the nature of the of these and do provide certain answers that have come up with so today we are going to look at the views of this French philosopher by the name of Rene Descartes now some of you may actually have heard of him he's the one he's the 16th century philosopher that came up with that famous phrase I think therefore I am we are going to look at that phrase later on in the semester but for today we are just going to look at his views of metaphysics his view of the nature of reality so um for Descartes he some his thoughts about his thoughts his metaphysical views by talking about this thing called substance so um you know the for Descartes he believes that the world of this can be divided into some really basic things that exist and which make up the building blocks of reality and he believes that most basic building block of reality is substance so they can't define a substance as a thing which so exist that it needs no other thing in order to exist now which is a narwhal saying that the substance is that most basic thing of the most basic unit of reality that it is so basic they can innovate and independently exist on its own so according to Descartes there are three basic kinds of substances and the three kinds of substances are God mind and body now um God is the you know according to Descartes our God exists and God is the most basic thing in the sense that he is able to exist without needing anything else to exist now you are you got this idea from earlier philosophers like Aquinas and you are probably familiar this from you know from thinking from reading about - a couple of weeks ago so besides God there is also mine and body now mine and body are strictly speaking not as basic as God because they had they have to have been created by God to come into existence no um let's start with mind so according to Descartes mind is a thinking and unexpended substance we all have minds we all have mental experiences and our mental experiences you know we are consists of thinking certain thoughts having certain feelings and perceiving certain things and you know that mental experiences are they are their nature is yesterday Emile well thoughts content they do not exist in space so strictly speaking or even the brain is not mine the brain is actually part of the body it is because the brain is something that exists in space whereas mine is not something there exists in space which brings us to the next substance which is body no body of which the brain is a part of is something that is unthinking and extended no body doesn't just refer to our physical bodies it also refers to things that exist in the physical world like chairs and tables and automobiles and things like that so body the the main characteristic of body is that it is unthinking and extended it is extended because it occupies a length breadth and depth in space it is unthinking because because it is not mine so so for the cart there are these three substances God mind and body so the cart is the first philosopher in history to come up with this distinction between mind and body of philosophers before him um like Aquinas and Aristotle and Plato basically you know assume that there is no problem with being able to know the world so that in bother to find to distinguish between mind body now um so they can't was the first person to make this distinction and we see that this distinction has carry on to today because even today we very unproven programmatically assumed that there is a distinction between mind and body however um undercuts view that there is of mind and body if you take as distinction between mind body gives rise to certain problems and these problems are problems that we actually haven't been able to solve even today so there are two main problems with them are we making a distinction between mind body two problems so the first problem is this if you make a distinction between mind body how is my body interaction possible how do you explain the interaction between mine and body um again in our common sense view if you ask the common person he will tell you that you know there is no problem with believing that there is an interaction between mind and body I mean on a very common-sense view if I think I'm going to extend my fingers now look my fingers extend if I want to curl my fingers into a fist because into a fist so there is this only we kind of naively and unproblematically assume that you know whatever my mind thing is is translated into actions of my body so we assume that there is no problem between mind body interaction or you know when I look out the window and see a tree I am prominently assumed that I naively assume that there is a physical object called tree out there then light bounces of the trees which impacts my optic nerves and causes me to see the tree but you must remember that the tree and the optic nerve of our body there are physical things whereas the mice in the tree is a mental experience so again if you think about it carefully how just how does the physical thing that is the tree and the light waves cause me to have this mental experience or how does mind cause my caused me to have to undertake this action of curling my hands into a fist or extending my fingers this is a problem for Descartes and it should be a problem for us because remember that mine and body are supposed to have nothing common one is - understanding thinking and understand earth whereas body is unthinking and extender they are diametrically opposite from each other there is nothing in common so how can two things which have nothing in common possibly in the rev each other and unfortunately yeah well I mean maybe fortunately many philosophers have tried to come up with an answer to this question over the centuries there is no space here to come in to try to answer this question but in my next video which is online needs you will see that light needs of we voice another philosopher actually tries to give an answer to this question and it is a very interesting answer so for a moment we are gonna leave this first problem unsolved ok now let's look at the second problem mmm the second problem is the problem of other minds so what is the problem reminds well let's take me for four for example right now I'm sitting here in this room I'm looking at the camera I'm looking around and I'm seeing things in this room so I'm having mental experiences and from this mental experiences I can infer that there is a mind that is having all these mental experiences but even though I meet other people I can oh you know I cannot experience their minds I cannot experience things from their perspective and similarly you are unable to experience things from my perspective you are unable to see the things that I see now you are unable to think the thoughts that I think now so here's the the problem is that I am I'm kind of trapped in my own mind and you guys are trapped in your own minds - I can't be sure that there are other minds around that are responding to my words or my actions I can be added I can be sure that those other minds are really Minds and not just computers or zombies or robots in similarly you also cannot be sure that this this thing here that's talking to you right now is a mind you can be sure that I'm a mind and not just a robot or zombie because it is for the simple reason that you simply can get in and mine and see things from my perspective so you know if the my body distinction gives rise to the problem of other minds if the only thing I can experience are my own mental experiences how can I possibly be certain that our minds exist so briefly speaking you know to summarize everything um take heart my body distinction is a very important distinction in the history of philosophy it is a distinction that we are familiar with and which we continue to use today now we unproblematically assume that there is a distinction between mind and body but that however leads to the unfortunate problem which is that we we are unable to account for how my own body interact we are also unable to account for how can there be other minds so Descartes philosophy is a way you can say it's a mix back there are there is a very influential of a worldview which we continue to hold today but at the same time it is also from with many you know difficulties now and these difficulties are the bigger is that we philosophers today still don't really have a satisfactory solution do oh okay so and that's all for right now I will leave you a review of this for now and think about all these thoughts for a little bit and stay tuned for my next video on blood needs thank you

Channel: Chinge Ang

Views: 4,149

Rating: 4.9259257 out of 5

Keywords: René Descartes (Academic), Metaphysics (Field Of Study), Philosophy (Field Of Study)

Id: HuFsg59SQuY

Length: 12min 25sec (745 seconds)

Published: Mon Sep 15 2014