Surlethe wrote:The future I can see demanding justification for it, but the past? Doesn't memory serve to make denial of the reality of the past prima facie ridiculous?
Let's not loosen what is meant by "reality" in this context. If what is meant is the denial that the past "had" existed in some limited sense, then yes, it is prima facie ridiculous. However, what's actually being denied is that the past is just as real as present, which is prima facie plausible, although it does lead to a fairly ugly ontology that forces interpreting statements of the past as statements about the present (present records especially).
Surlethe wrote:Speaking of thinking, here's a thought: suppose I make a similar prediction, "Kuroneko will reply to this post within twelve hours". Then the claim is one of the eventuality of your reply, yes?
Yes, but does this mean that when you made this statement, you were
already incorrect (and just didn't know it), or does it merely mean that when twelve came and passed, you were
made incorrect? Pragmatically, it makes almost no difference, but as far as the deductive force of your prior argument is concerned, it is a rather crucial distinction.
Surlethe wrote:I think there is a very subtle distinction between the statement "A reply by Kuroneko exists in the future" (which presumes the future exists), and "A reply by Kuroneko will exist after a given amount of time has elapsed" (which does not, I don't think -- it only presumes that time will continue to elapse, and makes a prediction about the current state of things after so much time has elapsed). I'm obviously having trouble articulating the distinction (real or imagined), though.
Given the standard format of weather predictions regarding rain done today, these predictions are never wrong, except in a negligibly small number of cases. Not because they predict rain with near-unerring accuracy, but rather because they don't--a typical weather report gives a probability of rain instead. Perhaps that's all that can be known, even if the state of the whole universe is known and arbitrarily high processing power is available. Put another way, there is a hidden assumption in your argument that the future can be known in absolute terms if sufficient information about the present state is available, and this assumption is far from being unquestionable. If it's not part of the class of things that can be known beyond probabilities no matter how much present information is available, there is no problem in an omniscient being not knowing it in absolute terms.
Surlethe wrote:Out of curiosity, how is "obvious" defined in this sense?
As far as I was concerned, something along the lines of "not requiring substantial evidence to justify."
Surlethe wrote:Saying a given proposition regarding the future (I want to say all propositions regarding the future are predictions, but I'm not entirely sure if that follows) is true or false iff it is true or false respectively in every possible outcome strikes me as almost tautological.
Nevertheless, it is far from tautological. Perhaps you're treating "iff" as if it was a mere "if". The implication is bidirectional; what it implies is that statements regarding the future that are not themselves tautologies or inconsistencies are
incapable of being either true or false in the absolute sense (regardless of human limitations of knowledge). And that is definitely not a tautology, but the essence of the determinism/indeterminism distinction.
Surlethe wrote:Ah, I see. I would tend to think, however, that responsibility for a particular action implies the ability to have done otherwise; doesn't determinism remove that, regardless of whether or not the decision-making process is divorced from the body? Or is there a point I've missed along the way?
When one typically talks about being "forced into" performing some action, the most relevant part is whether the situation they were in absolves them from moral culpability and/or puts it onto someone else. Shooting someone because he or she were about to kill you is much more morally acceptable than shooting someone because he or she cuts in line in a grocery store. Either way, the decision to shoot was made by an agent, and morality determines whether or not it was an appropriate response to the given stimuli. I'm having trouble seeing how determinism is supposed to undermine this. On the other hand, I've never successfully performed any action other than exactly whatever it was that I did, and have rather grave doubts that anyone else has either, so I'm not certain what this nebulous "ability to have done otherwise" actually means or why it is necessary to postulate it. Rather, it seems like a lot of metaphysical baggage for no substantive gain.