The philosophy and psychology of death seem weirdly under-discussed - particularly by the wider silicon valley community, given how strongly anti-death many people in it are. This post is an attempt to think through some relevant considerations, primarily focused on my own intuitions and emotions. See also this old blog post - I mostly still agree with the points I made in it, but when thinking about it now I frame things pretty differently.

Fearing death, loving life

Let’s first distinguish two broad types of reasons for wanting to avoid death: fearing death, and loving life.^[1] Perhaps these seem like two sides of the same coin - but, psychologically speaking, they feel very distinct to me. The former was particularly dominant when I was in primary school, when a part of me emerged that was very afraid of death (in a way that wasn’t closely linked to fear of missing out on any particular aspects of life). That part is still with me - but when it comes to the surface, its fear feels viscerally unpleasant, so I learned to suppress it pretty strongly.

Arguments for why death is bad usually focus on positive reasons - living longer allows people to experience more happiness, and more of the other good things in life. These have resonated with me more over time, as I started to think about death on a more intellectual level. However, one difficulty with these arguments is that many parts of me pursue goals in a fairly myopic way which doesn’t easily extrapolate to centuries, millennia, or longer. For example, it’s hard to imagine what career success or social success look like on the scale of millennia - and even when I try, those visions are pretty different from the versions of those concepts that I currently find motivating on a gut level. Extrapolating hedonistic goals is easier in some ways (it’s easy to imagine being happy for a very long time) but harder in other ways (the parts of me which care most about happiness are also the most myopic).

Dissolving fear

In practice, then, most of my motivation for avoiding death in the long term stems from fear of death. Although that fear comes out only rarely, I have a strong heuristic that fear-based motivation should be transmuted to other forms of motivation wherever possible. So what would happen if I talked more to the part that’s scared of death, to try and figure out where it’s coming from? By default, I expect it’d be uncooperative - it wants to continue being scared of death, to make sure that I act appropriately (e.g. that I stay ambitious). Can I assure it that I’ll still try hard to avoid death if it becomes less scared? One source of assurance is if I’m very excited about a very long life - which I am, because the future could be amazing. Another comes from the altruistic part of me, whose primary focus is increasing the probability that the future will in fact be amazing. Since I believe that we face significant existential risk this century,^[2] working to make humanity’s future go well overlaps heavily with working to make my own future go well. I think this broad argument (along with being in communities which reward longtermist altruism) has helped make the part of me that’s scared of death more quiescent.

Indeed, probably my main concern with my current attitude towards death is actually that I’m not scared enough about existential risk - I think that, if my emotions better matched my credences, that’d help motivate me (especially to pursue particularly unusual or ambitious interventions). This doesn’t seem like a crucial priority, though, since my excitement- and interest-based motivations have been working fairly well so far (modulo some other productivity gaps which seem pretty orthogonal).

Generalising to others

So far I’ve talked primarily about my own experience. I’m curious about how well this generalises to other people. It seems like fear of death is a near-universal emotion (it’s striking that the first recorded story we have is about striving to escape death), but my guess is that most people have it much less strongly than I did.

Since most people aren’t very openly concerned with avoiding death in the long term, I feel uncertain about the extent to which they’ve suppressed versus dissolved that fear. My guess is that in western societies most people have mainly suppressed it, and that the hostility they often show to longevity research or cryonics is a psychological defense mechanism. If so, then overcoming those defense mechanisms to convince people that death is not inevitable might unlock a lot of suppressed excitement about the future. However, I’m wary of assuming that other people are too similar to me - perhaps other people’s fear of death is just more myopic than mine.

There also seem to be some people who started off with a long-term fear of death, then dissolved it, usually by significantly changing their conception of personal identity - via meditation, or drugs, or philosophical argument. The big question is whether this change is more like an empirical update, or more like a value shift (to be clear, I don’t think that there’s a bright line between the two - but something can be much more like one or the other). If the former, then perhaps fear of death is just a “mistake” that many people make. Whereas the latter suggests that death is really bad according to some people’s values, and mostly fine for others, even though they may in other ways be psychologically similar. Both of these conclusions seem a bit weird; let’s try to get a bit more clarity by digging into arguments about personal identity now.

Continuity of self

The core question is how much we should buy into the folk view of personal identity - the view that there’s a single “thread” of experience which constitutes my self, where I survive if that thread continues and “die” if it breaks. I consider thought experiments about duplicates to provide strong evidence against this position - it seems very compelling to me that, when two identical copies of myself are created, there is no fact of the matter about which one is “really me”. Insofar as many people have intuitions weighing the other way, that’s probably because we evolved in an environment where identical duplication didn’t happen. In a future where duplication exists, and we continue being subject to evolution, I can easily imagine the mental concept of survival-of-self being straightforwardly replaced by the concept of survival-of-a-copy-of-myself.

The main alternative to caring about continuity is caring about level of similarity - identifying with a successor if they are sufficiently psychologically similar to you. This might leave you identifying with many successors, or ones that are very disconnected from you in time or space. However, it’s also consistent with identifying only with successors with a level of similarity that, in practice, will only be achievable by copying or uploading you^[3] (although I expect that really buying into the similarity theory of personal identity will make most people more altruistic, like it did for Parfit).

The strongest argument in favour of the folk view arises when considering large universes, like quantum multiverses or spatially infinite universes. In a quantum multiverse there are many copies of myself, and I tend to experience being the ones with more measure. But what does that even mean? If I expect that N slightly different copies of myself will branch off soon, and all of them will have the experience of being me, how can I anticipate being more likely to “find myself” as a given one of them? There's something here which I don't understand, and which makes me hesitant to fully dismiss the idea of a thread of experiences (a confusion which Yudkowsky explores in these two posts). I think the appropriate response is to be cautious until we understand this better - for instance, I would currently strongly prefer being non-destructively rather than destructively uploaded.

Generalising to society

When we stop thinking on an individual level and start thinking on a societal level, many more pragmatic considerations arise - especially related to how widespread longevity might shift the overall balance of power in the world. I do think these are important; here, though, I want to focus on a couple of broader philosophical considerations.

I previously talked about the part of myself which wants to make the future amazing. Partly that stems from imagining all the different ways in which the world might dramatically improve, including defeating death. Partly it’s an aesthetic preference about the trajectory of humanity - I want us to flourish in an analogous way to how I want to live a flourishing life myself. But there’s also a significant utilitarian motivation - which is relevant here because utilitarianism doesn’t care about death for its own sake, as long as the dead are replaced by new people with equal welfare. Indeed, if our lives have diminishing marginal value over time (which seems hard to dispute if you’re taking our own preferences into account at all), and humanity can only support a fixed population size, utilitarianism actively prefers that older people die and are replaced.

Now, I don’t think we’ll hit a “fixed population size” constraint until well after we’re posthuman, so this is a pretty abstract consideration. By that point, hopefully we won’t need to bite any bullets - we could build a flourishing civilisation which extrapolates our more human-specific values as well as possible, and also separately build the best utilitarian civilisation (assuming we can ensure non-conflict between them). But I’m also open to the idea that the future will look sufficiently weird that many of the concepts I’ve been using break down. For example, the boundaries between different minds could blur to such an extent that talking about the deaths of individuals doesn’t make much sense any more. I find it hard to viscerally desire that for myself, and I expect that most people alive today are much less open to the possibility than I am, but I can imagine changing my mind as we come to understand much more about how minds and values work.

1. ^{^}

   Upon reflection, I might also add a third distinct motivation - the celebration of immortality. I get this feeling particularly when I read fiction with very long-lived characters. But since it's much weaker than the other two, I won't discuss it further.

2. ^{^}

   At least double digit percentage points, although my specific estimate is pretty unstable.

3. ^{^}

   On a side note: I feel very uncertain about how much information about my brain (in the form of my blog posts, tweets, background information about my life, etc) would be sufficient for future superintelligences to recreate me in a way that I’d consider a copy of myself. I haven’t even seen any rough bounds on this - maybe worth looking into.