8.4 Persons, Humans and Brains

again coming back to the distinction between persons and animals we might want to collapse that we might want to say maybe we don't need that distinction maybe we should just go with identity of physical organisms we can see that why in the 17th and 18th centuries they might not have been Keen to do that because it does seem to to um ruin the prospects for an immortal Soul or an immaterial soul and that of course could be a reason for people not wanting to do that nowadays but suppose we don't mind about that suppose we don't believe in immaterial souls in that case we might be tempted to collapse the distinction between person and organism but this does have significant implications if I was once a fetus and this human organism was once it seems to follow that I once wasn't a person to be a person you need to have some significant mental life or at least that is how most people would understand the notion of person maybe there will come a time when this physical organism is still operating as an organism but has no con conscious life maybe at the end of my life this will be an physical organism after the personhood has gone so it might seem to follow that being a person is as it were an accidental property of mine rather than an essential property and that might seem to be rather an uncomfortable position to think of myself as not necessarily a person okay suppose we bring these together suppose we're impressed by that thought could we not then identify the person with the developed functioning brain rather than the whole organism so in other words maybe we want to say that a person only comes into existence not when the embryo um is formed not at conception not even when there's a very early fetus but when the brain starts developing when Consciousness emerges that's when a person comes along and the person is to be identified with the developed functioning brain rather than with the whole organism so that can make sense of the Williams cases where the brain gets transplanted maybe there we fairly unpraised so when you have a brain transplant actually it's a body transplant not a brain transplant you can imagine um some devious clever person approaching somebody who's a bit simple uh but happens to be blessed with an extremely good body uh and persuading them that it would be greatly to their advantage to have this wonderful brain transplanted into their body and thus the uh the old genius gets rejuvenated okay so this solves some of the problems but unfortunately things aren't so simple split brain cases for example if the nerves between the hemispheres of the brain are surgically cut that is a procedure that can be done I think treatment can be an extreme treatment for epilepsy for example then you can have a single brain giving rise to two conflicting behaviors you can find the two hands do different things they no longer coordinate okay let's build a problem case from this suppose we have a single brain that's split and put in two bodies each half of the brain can in certain circumstances survive alone suppose uh that that is if part of the brain is destroyed one can make do with less suppose it be became possible to transplant the two halves into separate bodies in that case you'd have two new persons both having brain and memory continuity with the original okay so both the two persons would remember being me there would be at least significant continuity over both of both brain and thought what do we say then well maybe if this happened we'd actually give up the notion of strict personal identity maybe if this became a common thing we would no longer think of personal identity as all or nothing and Derek parfit actually suggests this as uh the way we ought to think about personal identity it's a matter of degree and we can bring Lock's forensic thought in here if what matters is our concern uh both moral um and utilitarian as it were about our future self what matters about personal identity what matters about me tomorrow is that I today care about that person and will make plans on the assumption that that is me then that seems to reflect the way we would judge about split brain cases suppose I knew that I was going to my brain was going to be split and put into two separate bodies I mean let's suppose I've got some medical condition my you know I've done too much philosophy and my brain is beginning to fall apart and the solution is to cut it in two and give each half a separate life I don't know quite how I'd negotiate things with my wife in these circumstances but uh maybe maybe we decide that's the best thing to do I think I'd want to make sure that both of those individuals were provided for we would care about both future selves so maybe thinking of personal identity as a matter of degree would be an appropriate thing to do in those circumstances and I want to leave you with a concept which I think is a a particularly useful one for thinking about some of these problems not only personal identity but other Concepts in philosophy as well Fredick vicman who spent many years at Oxford in fact uh yeah a lot of them did coin coined this term um for Concepts which become vague in radically novel situations and he actually suggested that most empirical concepts are like this that with most of our ordinary everyday Concepts if you dream up dramatically radical novel situations it becomes very unclear how to apply them and the thought here is not that there is that it's a difficult question how to apply them and we have to think a lot about it to get to the truth rather the thought is that maybe there is no correct way to apply them it raises a new question so let me give you an example it used to be when I was growing up taken for granted that marriage always could only involve one man one woman of course you could have things like divorce and so forth but marriage applied straightforwardly to a man and a woman you couldn't marry you couldn't have marriage between two men you couldn't have marriage between two women that simply wouldn't be marriage whatever it was okay lines have been blurred but in think yourself into that situation and then ask okay suppose somebody's had a sex change operation what then can a man marry a sex changed woman born a woman now a man can they marry what about the other way around born a man now a woman can a man man marry her her and you can see that it's just left radically unclear when people as it were invented the concept of marriage the idea of a sex change of someone changing their sex during the course of their life was simply out of the question so there wouldn't have been any thought about this situation the concept of marriage took for granted that sex was stable and if it isn't maybe there's no right answer as to how that concept should be taken forward maybe one could answer in different ways maybe we're going to invent have to invent A New Concept to deal with this kind of situation but in many cases what we do when we have a radically new situation we reinterpret our old concept or take having a conversation we know what having a conversation with someone is like okay and then the telephone comes along is that having a conversation well sort of yes seems pretty close what about email is that having a conversation you can see that as technological change takes place it may become radically unclear how we should adapt our Concepts to cope with it and it may be that personal identity is a concept which takes for granted all sorts of things which in the vast majority of cases are true of us we do the the retain the same Consciousness in the same body continuously developing through life it may be that when we dream up these puzzle cases we are inventing situations to which there is in fact no right answer if such things were to become commonplace then maybe we'd have to adapt our concept on that note I'm going to finish thank you very much for staying to the end

Channel: University of Oxford

Views: 20,577

Keywords: oxford univeristy, lecture, peter millican, philosophy, identity, locke, hume, mind, body, waismann, parfit

Id: 9HhWqBJtPP8

Length: 11min 3sec (663 seconds)

Published: Thu Apr 14 2011