In comments to yesterday’s post about my favorite Many-Worlds story, a couple of people mention “All the Myriad Ways,” a Larry Niven short story. I don’t think I’ve ever actually read the story, but it gets brought up all the time, so I’m familiar with the concept. It’s an angle on Many-Worlds that I don’t like, and has something in common with the central conceit of Inception, which is also not high on my list of literary tropes, though my reaction isn’t anywhere near as negative as Scott’s.
If you’re not familiar with it, here’s the summary from Wikipedia:
A police detective, pondering a rash of unexplained suicides and murder-suicides occurring since the discovery of travel to parallel universes, begins to realize that being if all possible choices that might be made are actually made in parallel universes, people will see their freedom of choice as meaningless. The choice not to commit suicide, or not to commit a crime, seems meaningless if one knows that in some other universe, the choice went the other way. They therefore kill themselves or commit the crime, because they abandon the sense of choice.
This is a dramatization of a philosophical idea that fails for me on such a fundamental level that I can’t really take it seriously. I just don’t understand how the existence of other universes has any effect on me. In the end, my personality is the result of a myriad of choices I’ve made in my life, and some alternate-universe version of me who made different choices is a different person. And the notion of committing suicide at all, let alone over something as daft as the existence of parallel universes, is sufficiently foreign to my mindset that I can’t really consider anyone who would do that to be “me” in any meaningful sense.
This is true for the actual Many-Worlds interpretation, in which the alternate versions would be completely inaccessible, and it goes double for parallel universes that you can actually visit. In the first case, you could at least make the case that the alternates are using the same fundamental particles I am, just in a different branch of the wavefunction. If you can visit their home worlds, though, they are absolutely and unequivocally (to my mind) other people. And while other people who I’ve never met deciding to commit suicide is kind of a bummer, it’s not something that’s going to ruin my life.
This business of duplicates is a variant of the question “What if we don’t have free will?”, another philosophical question that I just can’t take seriously. If we do have free will, then I have an obligation to choose to act in an ethical manner (however you define ethics). If we don’t have free will, by definition, there’s nothing I can do about it, so it’s hardly worth expending any energy on (not that I could choose to expend energy on it or not).
The question at the heart of Inception– “What if we’re actually dreaming?”– is in a similar place. If everything I seem to see around me is actually a flawless illusion, there’s nothing I can do about it, so I might as well carry on as if what I see is actually real. There isn’t really any sensible alternative course of action, absent some really convincing proof to the contrary.
This attitude probably renders me incapable of doing certain kinds of theory– I find Boltzmann brains and the anthropic principle pretty worthless as well– but, you know, I can live with that.
That’s the reason why I really like “Divided by Infinity”, as I said yesterday: the effectiveness of the story doesn’t come from any abstract philosophy, but from a feature inherent in the notion of Many-Worlds style parallel universes. It’s also got a sort of inevitability to it that “All the Myriad Ways” and similar stories lack– there’s nothing the narrator could do to escape the story. Most of the time I read alternate-universe stories, I’m left thinking “You know, in the universe where you’re not a complete dope, this is a really boring story.” Wilson avoids that issue, and the result is far and away the best story about these ideas I’ve ever seen.