I meant that learning the universe is deterministic should not turn one into a fatalist who doesn’t care about making good decisions (which is the intuition that many people have about determinism), because goals and choices mean something even in a deterministic universe. As an analogy, note that all of the agents in my decision theory sequence are deterministic (with one kind-of exception: they can make a deterministic choice to adopt a mixed strategy), but some of them characteristically do better than others.
Regarding the “changing the future” idea, let’s think of what it means in the context of two deterministic computer programs playing chess. It is a fact that only one game actually gets played, but many alternate moves are explored in hypotheticals (within the programs) along the way. When one program decides to make a particular move, it’s not that “the future changed” (since someone with a faster computer could have predicted in advance what moves the programs make, the future is in that sense fixed), but rather that of all the hypothetical moves it explored, the program chose one according to a particular set of criteria. Other programs would have chosen another moves in those circumstances, which would have led to different games in the end.
When you or I are deciding what to do, the different hypothetical options all feel like they’re on an equal basis, because we haven’t figured out what to choose. That doesn’t mean that different possible futures are all real, and that all but one vanish when we make our decision. The hypothetical futures exist on our map, not in the territory; it may be that no version of you anywhere chooses option X, even though you considered it.
but some of them characteristically do better than others.
A fair point, though I would be interested to hear how the algorithm described in DT relate to action (it can’t be that they describe action, since we needn’t act on the output of a DT, especially given that we’re often akratic). When the metaethics sequence, for all the trouble I have with its arguments, gets into an account of free will, I don’t generally find myself in disagreement. I’ve been looking over that and the physics sequences in the last couple of days, and I think I’ve found the point where I need to do some more reading: I think I just don’t believe either that the universe is timeless, or that it’s a block universe. So I should read Barbour’s book.
Thanks, buy the way for posting that DT series, and for answering my questions. Both have been very helpful.
Does that make more sense?
It does, but I find myself, as I said, unable to grant the premise that statements about the future have truth value. I think I do just need to read up on this view of time.
Thanks, buy the way for posting that DT series, and for answering my questions. Both have been very helpful.
You’re welcome!
I would be interested to hear how the algorithm described in DT relate to action (it can’t be that they describe action, since we needn’t act on the output of a DT, especially given that we’re often akratic).
Yeah, a human who consciously endorses a particular decision theory is not the same sort of agent as a simple algorithm that runs that decision theory. But that has more to do with the messy psychology of human beings than with decision theory in its abstract mathematical form.
I meant that learning the universe is deterministic should not turn one into a fatalist who doesn’t care about making good decisions (which is the intuition that many people have about determinism), because goals and choices mean something even in a deterministic universe. As an analogy, note that all of the agents in my decision theory sequence are deterministic (with one kind-of exception: they can make a deterministic choice to adopt a mixed strategy), but some of them characteristically do better than others.
Regarding the “changing the future” idea, let’s think of what it means in the context of two deterministic computer programs playing chess. It is a fact that only one game actually gets played, but many alternate moves are explored in hypotheticals (within the programs) along the way. When one program decides to make a particular move, it’s not that “the future changed” (since someone with a faster computer could have predicted in advance what moves the programs make, the future is in that sense fixed), but rather that of all the hypothetical moves it explored, the program chose one according to a particular set of criteria. Other programs would have chosen another moves in those circumstances, which would have led to different games in the end.
When you or I are deciding what to do, the different hypothetical options all feel like they’re on an equal basis, because we haven’t figured out what to choose. That doesn’t mean that different possible futures are all real, and that all but one vanish when we make our decision. The hypothetical futures exist on our map, not in the territory; it may be that no version of you anywhere chooses option X, even though you considered it.
Does that make more sense?
A fair point, though I would be interested to hear how the algorithm described in DT relate to action (it can’t be that they describe action, since we needn’t act on the output of a DT, especially given that we’re often akratic). When the metaethics sequence, for all the trouble I have with its arguments, gets into an account of free will, I don’t generally find myself in disagreement. I’ve been looking over that and the physics sequences in the last couple of days, and I think I’ve found the point where I need to do some more reading: I think I just don’t believe either that the universe is timeless, or that it’s a block universe. So I should read Barbour’s book.
Thanks, buy the way for posting that DT series, and for answering my questions. Both have been very helpful.
It does, but I find myself, as I said, unable to grant the premise that statements about the future have truth value. I think I do just need to read up on this view of time.
You’re welcome!
Yeah, a human who consciously endorses a particular decision theory is not the same sort of agent as a simple algorithm that runs that decision theory. But that has more to do with the messy psychology of human beings than with decision theory in its abstract mathematical form.