I have a mother with alzheimer dementia in a very advanced stage and she is unconscious about anything is happening around her. I think she is alive phisically but not a conscious being, she acts by instincts, grabbing a piece of bread or crying when she needs something, like a baby or an animal. Cant talk, dont know who she is or anything... I cant stop asking myself wether she is "alive", alive here meaning as a conscious human being. If I was religious I would ask where did her soul go?? Is it still there? Is it only her body what is left? Is all mad people also "alive"under this terms? What about very young children (who hasnt developed self awareness yet)? What about people who lives in auto pilot all their life and never question ther existence? Actually when do we start being "alive" under this concept? "I think therefore I am" Sorry for the long lines, I hope I explained myself. Thank you in advance. Juan C.

It is very sad to hear your story. I can give a guess about the awfulness of what you are going through, but I am more certain that I cannot appreciate the full daily horror for you. Your question is a most reasonable one. Is your mother "alive"? It is interesting that you feel obliged to put this word in scare quotes. It is something that "you can't stop asking yourself". So there is something very important here, an important issue. But you have also answered your own question, or part of it. Let us distinguish between the mental and the physical. Is your mother alive physically? Her body is not dead, if we can put it that way. Is she alive "as a conscious being"? Here you give your own answer: ' . . . she is unconscious about anything [that] is happening around her.' I think perhaps you should say that she is conscious only of the most immediate and restricted domain. That perhaps is part of the reason the question is difficult. She is conscious, but not in a full sense. The whole difficulty about...

Here is a question. Say I want to live forever and constantly move my brain from one body to another, so I never age. I also replace non functioning parts of my brain with new ones made with stem cells. Eventually after living for a long enough time my brain is no longer anything like the original except for its collective memories. Would that thing still be me? To take it a step further I create clones of myself and each of them has a small part of my originals brain. Would I still exist? Or I created a collective consciousness in which I am able to communicate to each of my clones and we are able to share our experiences in one big cloud. What does that even mean for me? Am I even the same person or something completely different? These problems have been really bugging me and I am just trying to see if anyone has any answer.

Often with questions that are composed of multiple further questions ("Here is a question", you write . . . - it's not - I count four question marks!) it helps to take just one, and deal with it carefully, before moving on to the next. Of course some of the sub-questions will generate further questions, but that simply means that some patience is required. For example, 'I move my brain from one body to another, so I never age.' Why does it follow that you never age? If you retain your memories (line 3) and add to them, then you are changing and aging, psychologically. So you must mean that you don't physically age. But the brain does age. And why is it that 'I never age' follows from 'I move my brain from one body to another'? That seems to assume that who you are is a matter of having the same brain. Is that right? And if it is, then if as you say 'after living for a long time my brain is no longer anything like the original' then you are not after all the same person, so the question goes away. A...

My question involves the word "same" apropos to identity vs. comparison, especially to the base case of a particular induction proof. I was trying to find the flaw in the induction for: "P = All horses are the same color. Base Case: P(1) = One horse is the same color as itself. Induction: We have n+1 horses. Take any one away, and the rest will be the same (because of P(n)). Since it didn't matter which we took away, all horses must be the same." I posit that the flaw in this proof isn't simply the lack of "sameness" overlap in the P(2) instance, but in the choice of base case and use of the word "same." I say that there needs to be a comparison (i.e., 2 or more unique objects) in the base case to use the word "same" as it is in "P". If I say Horse A is the same color as Horse A, and you say Horse A is the same color as Horse B, are we really using the word "same" in the same sense? If not, doesn't it follow that it's better not to use them interchangeably in an induction proof such as the one above? If...

Wait! You have proved the base clause all right, but where is your proof of the inductive step? Is it that if you remove the inductive steps, you are left with a true base step, which is true? But this is obviously not a good deductive proof. I think too you may be mixing up mathematical induction, which is a form of deduction, and induction in the sense of generalization, which is not a form of deduction. So your paradox is not a paradox, and it doesn't make trouble for the word "same". What am I missing?

Hi, I am working on a story which revolves around the idea of memory implantation. So, I am wondering: If Person A commits a crime, then they have the full memory and emotions of that crime erased from their mind and then that memory is placed into the mind of Person B so they believe they committed the crime (Even remembering the thoughts and feelings as they committed it) who is guilty of the crime? Kind Regards, Lee

It seems that you have answered your own question. You write, "If Person A commits a crime . . . who is guilty of the crime?" Person A, certainly, since you write on the supposition that "Person A commits a crime . . ." Of course A isn't legally guilty until he's found guilty by a court. But I think you mean, 'Who committed the crime?' That was A. Should A be tried? He is suffering some kind of memory loss, so there are issues of competence. On the whole, if I have forgotten about a crime I have committed, it doesn't seem enough to make me innocent. A faulty memory is hardly a good defence.

If a person has a multiple personality disorder, are they one individual, or several individuals?

What used to be called multiple personality disorder (MPD) is now called dissociative identity disorder (DID) in DSM, the Diagnostic and Statistical Manual of Mental Disorders , and the change in terminology may reflect a possible change in thinking. A personality (e.g. a television personality) is in one sense a person, but generally I and my personality are not the same (Same what? Same entity, presumably, if that is any help!) In any case, since my personality might change considerably over time, while I remain the same person or the same individual (I assume that individual and person , as they are applied to human beings, are equivalent concepts), the two cannot be identical. And most of us do exhibit slightly different personalities, for example at home and at work, or with friends and with superiors. Those who have a mixed ethnic or national heritage can sometimes find that they have two personalities, say one English and one Indian. They may...

Philosophers debate persistence conditions for personal identity because everything about us seems to change, including our cells, our memories, and our bodies. But DNA doesn't change and it codes for specfic traits in every cell of the human body. It's true that we experience changes in the way phenotypes are expressed in particular experiences or memories, but why not conclude that DNA is the ultimate source of personal identity? Philosophers don't seem to give this biological candidate serious consideration. Can you tell me why?

DNA does change. There are "point mutations", for example, in which say a single nucleotide changes, say from guanine to cytosine. . . . CTG TCA . . . becomes . . . CTG GCA . . . If there is a strand of DNA that suffers such a change, is it then not the same strand of DNA ? This is exactly like the question whether persons become different persons if they lose say half a finger. And now we have the problem of DNA identity. When are two descriptions sufficiently similar to count as descriptions of the same strand of DNA ? Anthony Quinton has the general issue right, in a 1962 article in the Journal of Philosophy called "The Soul": 'No general account of the identity of a kind of individual thing can be given which finds that identity in the presence of another individual thing within it. For the question immediately arises, how is the identity through time of the identifier to be established? It, like the thing it is...

We can only live in this "here&now moment"...in fact, there is no way we can ever live out of "IT"...is it not?

'We can only live in this "here and now" moment . . . in fact , there is no way we can ever live out of it . . . is it not?' I am not sure what is supposed to meant by living in the present instant ("moment" I think has more to do with action). Living at an instant seems as impossible as living at some other time, because there isn't even time to draw breath in an instant. In any case I do not believe that there is something called "the present instant", so I don't see how we could live in it (at it?) It (the present instant) is an abstraction, and it is not, in reality! I do believe there are present times, though, such as the present day or hour. The trouble with the instant is that it is not a time.