“My future is FA, because my current state is A.” This is standard causality: A causes FA by a sequence of steps that follow the laws of physics.
“My history was HA, because my current state is A.” This is anthropic reasoning: technically, it was HA causing A by a sequence of steps, but if we ask “given that I am currently A, how does this limit my possible histories?” the answer might be that only such history is HA.
These two are not the same, but an exact explanation would require explaining exactly what is the difference between the past and the future, how the arrow of time works, etc., which I am not really sure myself how it works, and would probably involve making statements about quantum physics and other complicated things.
It might also work differently in different universes. For example, imagine a deterministic universe of the Game of Life, assuming that it can contain intelligent beings similar to us. For a current state A, there is only one future FA. But there could have been multiple different histories HA that resulted in A. (Or perhaps there was no such history, and the universe was created just now.)
The short version is that for practical purposes, the future and the past, causality and anthropic reasoning, seem to work differently.
Let’s look at the mechanism closer:
“My future is FA, because my current state is A.” This is standard causality: A causes FA by a sequence of steps that follow the laws of physics.
“My history was HA, because my current state is A.” This is anthropic reasoning: technically, it was HA causing A by a sequence of steps, but if we ask “given that I am currently A, how does this limit my possible histories?” the answer might be that only such history is HA.
These two are not the same, but an exact explanation would require explaining exactly what is the difference between the past and the future, how the arrow of time works, etc., which I am not really sure myself how it works, and would probably involve making statements about quantum physics and other complicated things.
It might also work differently in different universes. For example, imagine a deterministic universe of the Game of Life, assuming that it can contain intelligent beings similar to us. For a current state A, there is only one future FA. But there could have been multiple different histories HA that resulted in A. (Or perhaps there was no such history, and the universe was created just now.)
The short version is that for practical purposes, the future and the past, causality and anthropic reasoning, seem to work differently.