To those who don’t know the Green Line T (subway) in Boston, the tracks are street-level and non-electrified, so you can cross over them. The possibility exists to get run over fairly easily, and today I just missed a situation that could have led to me (and another person) getting squished. I had just left a train, and I darted across the tracks in front of an oncoming train, but with plenty of room. However, another person was crossing in the other direction in order to get on the train I just left. Anyway, we came within inches of colliding with each other, which could very easily have landed one or both of us on our backside on the tracks. Afterwards, I had visions of the unfolding event: we collide, then one of us heroically pulls the other from the tracks just in the nick of time. OR: we collide, then one of us gets squished.
As I walked away from the situation, thinking these things through, I thought to myself, “well, maybe in a parallel universe we did collide, and in that universe, I’m dead!” Then I pondered some more and I thought, “Glad I’m in this universe!” Then I thought some MORE (and this was even before my first cup of coffee!) and figured that the only reason I’m still alive is because I happen to be in a universe in which I haven’t yet died. That depressed me. So I kept thinking, and I wondered if maybe our consciousness just kind of follows along with the universe in which we haven’t yet died. Then I thought, “what the hell do I know about consciousness, anyway? I don’t believe in any hokey-pokey new-age baloney about ultra-consciousness, souls, etc.” So now I don’t know what to think, which might just be better.
Sure, you’re lucky that this isn’t the universe in which you get run over. But remember: this also isn’t the universe in which you heroically save a life and get The Key To The City or whatever the hell happens when you save a life in the real world.
By strange coincidence, something very similar happened to me (at least in this universe) yesterday when crossing the road.
Think about that a bit more; your consciousness would also transfer from the you that dies from some disease or other to the you that pulls through; it should also transfer from the you that dies of old age to the you that is saved from death by old age by the timely invention of an immortality drug.
Also, in all of these cases, there can’t just be two different universes and a simple binary bifurcation; there must be infinitely many. In one universe, you didn’t collide with the other guy, but you did notice he had a piece of spinach lodged in his front teeth, in another, you didn’t collide, but he had one less hair on his head, in another, the populations of his gut bacteria were slightly different, in another, one of the sodium pumps in a particular neuron in his brain acted upon a slightly different mix of ions. And so on, in fact given that there would have to be infinitely many different universes where every possible difference is played out, why would there be only one of each; there should also be infinitely many exact duplicates of each particular variation.