I posted the following comment in this thread, but it almost seems more appropriate here:
What would be the consequence of giving up the idea of a subjective thread of consciousness?
I wonder if believers in subjective threads of consciousness can perform a thought experiment like Chalmers' qualia-zombie thought experiment. I gather that advocates of the subjective thread hold that it is something more than just having certain clumps of matter existing at different times holding certain causal relationships with one another. (Otherwise you couldn't decide which of two future copies of yourself gets to inherit your subjective thread). So, advocates, does this mean that you can imagine an alternate universe in which matter is arranged in the same way as in our own throughout time, but in which no subjective threads bind certain clumps together? That is, do you think that "subjective-thread zombies" are possible in principle?
Just as in the Chalmers thought experiment, subjective-thread zombies would go around insisting that they have subjective threads. After all, their brains and lips would be participating in the same causal processes that lead you to say such things in this universe. And yet they would be wrong. They would not be saying these things because they have subjective threads, since they don't. And so, it seems, your insistence that you have a subjective thread also cannot have anything to do with whether you in fact do.
It seems that the idea of subjective-thread zombies is subject to all the problems that qualia zombies have. How do advocates of the subjective thread address or evade these problems?
The experience of a subjective thread of consciousness - let's call it STC - is pretty much the experience of experience, or qualia. So Chalmers' experiment is apt.
The relevant fact is that STC is purely subjective. The reason I think you and everyone else have STCs is because you say you do, and it's a simpler hypothesis than the one saying I'm different from everyone else. But the reason I think I have an STC is completely different: I know it from direct experience, which is pretty much by definition incontrovertible. (I may be mistaken about the real w...
From the dawn of civilization humans believed in eternal life. The flesh may rot, but the soul will be reborn. To save the soul from the potential adverse living conditions (e.g. hell), the body, being the transient and thus the less important part, was expected to make sacrifices. To accumulate the best possible karma, pleasures of the flesh had to be given up or at least heavily curtailed.
Naturally the wisdom of this trade-off was questioned by many skeptical minds. The idea of reincarnation may have a strong appeal to imagination, but in absence of any credible evidence the Occam’s razor mercilessly cuts it into pieces. Instead of sacrificing for the sake of the future incarnations, a rationalist should live for the present. But does he really?
Consider the “incarnations” of the same person at different ages. Upon reaching the age of self-awareness, the earlier “incarnations” start making sacrifices for the benefit of the later ones. Dreams of becoming an astronaut at 25 may prompt a child of nine to exercise or study instead of playing. Upon reaching the age of 25, the same child may take a job at the bank and start saving for the potential retirement. Of course, legally all these “incarnations” are just the same person. But beyond jurisprudence, what is it that makes you who you are at the age of nine, twenty five or seventy?
Over the years your body, tastes, goals and the whole worldview are likely to undergo dramatic change. The single thing which remains essentially constant through your entire life is your DNA sequence. Through natural selection, evolution has ensured that we preferentially empathize with those whose DNA sequence is most similar to our own, i.e. our children, siblings and, most importantly, ourselves. But, instinct excepted, is there a reason why a rational self-conscious being must obey a program implanted in us by the unconscious force of evolution? If you identify more with your mind (personality/views/goals/…) than with the DNA sequence, why should you care more for someone who, living many years from now will resemble you less than some actual people living today?
P.S. I am aware that the meaning of “self” was debated by philosophers for many years, but I am really curious about the personal answers of “ordinary” rationalists to this question.