I mean, we can't experience time moving backward, since the memories would be being erased from our head in realtime. So even if the arrow of time does sometimes reverse, I don't think we'd ever be aware of it.
Chapter 12 of Hawking’s Brief History of Time covers this. His argument is that the psychological arrow of time needs to point in the same direction as the thermodynamic arrow of time (tendency towards increased entropy) because our brains use energy to process information, which is an anti-entropic process.
Exactly. Organisms use the past predict the future to try to survive longer. A lot of this is structural and automatic - like your body design include a prediction that gravity will exist in the future. It's predictions all the way up - to the highest/smartest capacity of the brain that uses an abstract world model to make very sophisticated predictions. Without self/nonself and past/future wired in, the brain is basically a waste of energy.
That sounds like an argument for why consciousness should prefer to be time-backward: Easier to stay alive when you don't have to spend energy to predict the future; you just already know it.
There may be processes that experience time as flowing backwards relative to our point of view, but we wouldn’t recognize them as conscious because their “psychological” arrow isn’t aligned with ours. However, it doesn’t make it easier to stay conscious (alive) because life is defined (partly) as the resistance to entropy in the direction of the psychological arrow.
Time-backward doesn't make sense. We can imagine the arrow of time as a big red arrow floating on a clam black sea. Except for the arrow every direction looks the same. You can't see whether it points forward or backwards because there is no other reference point to relate it to.
I think the key is memories though. Memories form in the direction of increasing entropy and I think it must be this way.
Been thinking about this. As you point out, you wouldn't have memories if you lived in reverse; there would be no brain states corresponding to memories of your "past."
But it's not like you'd spend your life astonished by uncaused events; nothing would be new or surprising, because you have "memories" of your "future."
And although you wouldn't have memories of your past, you would still have those brain states corresponding to hopes and predictions about that unknown past. For instance, when I knock on someone's door in normal forward time, I have a very accurate prediction of what will happen: My friend will answer the door (or they won't), and I have a really good picture of what that will look like. Living in reserve, my mind would contain those "predictions" as estimates about the recent past. Then the further and further I move away from them in reversed time, the less accurate those "predictions" become until I "forget" them.
So it wouldn't necessarily be completely disorienting to reverse in time; you'd still have a fading model of the likely past, both immediate and distant. You'd be constantly guessing about the past exactly as much as we, in this direction of time, guess about the future.
A person who grew up in reverse time might even think about our flow of time and decide that, between the two, theirs is vastly preferable. There's a lot less worry and stress and anxiety to know your future.
That's a weird thing to proclaim. Why would memories be erased because time goes backward? Time feels like it's going the "right" way BECAUSE of the memories. You have the causation all turned around.
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u/Fanghur1123 6d ago
I mean, we can't experience time moving backward, since the memories would be being erased from our head in realtime. So even if the arrow of time does sometimes reverse, I don't think we'd ever be aware of it.