I agree; wherever there is paradox and endless debate, I have always found ambiguity in the initial posing of the question. An unorthodox mathematician named Norman Wildberger just released a new solution by unambiguously specifying what we know about Omega's predictive powers.
truth=opinion
I'd phrase it as "truth is subjective," but I agree in principle. Truth is a word for everyday talk, not for precise discourse. This may sound pretty off-the-wall, but stepping back for a second it should be no surprise that holding to everyday English phrasing would interfere with our efforts to speak precisely. I'll put this more specifically below.
But if e.g. you get in an accident and you lose your leg, nobody will have offered you an opinion, but nonetheless it'll be true that you'll be missing a leg.
This is actually begging the question in that you tacitly assume objective truth by using the standard English phrasing. That there is such a thing as an objective truth is precisely the conclusion you hope to establish. Unfortunately English all but forces you to start by assuming it. Again, carrying over the habits of everyday talk into a precise discussion is a recipe for confusion. We'll have to be a little more careful with phrasing to get at what's going on.
I'd first point out that when you say, "you lose your leg," you are speaking as if there is some omniscient narrator who knows "the objective facts of reality." Parent's point is exactly that there is no such omniscience. There are only individuals, including you and I, who have [subjective] experiences.
To get specific, we would have to identify who it is that witnesses the loss of Parent's leg. If you had said, "e.g. you find that you get in an accident and that you lose your leg," it would not be convincing to follow up with, "but nonetheless it'll be true that you'll be missing a leg."
We could all have witnessed (what we experience as) Parent losing a leg. It will be "true" for us (everyday talk), but none among us is an omniscient narrator qualified to state any more than what we experienced. Nowhere is any objective truth to be found. If we were to call it an "objective truth," we would simply be referencing the fact that all three of our experiences seem to match up. It would be at best an inter-subjective "truth," but this "truth" is a lie to someone else who thinks they see Parent with both legs still attached. To avoid confusion, we had best call it a subjective report or something. Hence, while perhaps not ideal, "truth=opinion" is not too bad a way to put it after all.
Any time you have a bias you cannot fully compensate for, there is a potential benefit to putting instrumental rationality above epistemic.
One fear I was unable to overcome for many years was that of approaching groups of people. I tried all sorts of things, but the best piece advice turned out to be: "Think they'll like you." Simply believing that eliminates the fear and aids in my social goals, even though it sometimes proves to have been a false belief, especially with regard to my initial reception. Believing that only 3 out of 4 groups will like or welcome me initially and 1 will rebuff me, even though this may be the case, has not been as useful as believing that they'll all like me.
He's making some interesting points, and he gets extra credit in my view for taking so radical a view while usually remaining reasonable. I find his railing against prediction to be puzzling, but his semantic points and discussion of Ptolemaic explanations have given me a lot to think about.
I also noticed that even some of his friendly, reasoned posts were being downvoted to the same extreme negative levels, which seems unwarranted. He has posted too much without familiarizing himself with the norms here, but he shows sincerity and willingness to learn and adapt. He got a little testy a few times, but he also apologized a lot.
All in all, with a few notable exceptions, it looks like he is getting downvoted mainly for unfamiliarity with LW posting style and for disagreeing with "settled science" (I myself am not too partial to that term). Perhaps also for some unconventional spellings and other idiosyncrasies.
I'm open to being corrected on this, but I think I have read this entire thread and I am pretty sure Monkeymind is not deliberately trolling. High inferential distance feels like trolling so often that it's almost a forum trope. I myself am enjoying some of his posts and the responses.
I'll change my mind if he continues with the present posting style, though.
You're making a ton of interesting points, but please succinctify (a lot!). I mean, let people reply and stuff. I feel sorry for you writing all that knowing almost no one will see it. It's obvious you're reading LW classic posts and making discoveries, and then immediately turning around and applying them, which is great. I just think you'd do well to steep yourself in the posting norms of this forum so you can participate in a more fruitful way. Again, I for one would like to hear well-reasoned radical views.
To be honest, you sound bitter or something, although given the difference of opinion being as radical as it is, that is pretty understandable (so are the downvotes, for the same reason). Maybe let it cool off for a bit. I have an interest in hearing what you think after you have spent more time here.
You remind me of Silas Barta, and I think we could use more people who radically disagree with major pieces of LW, because it is good practice if nothing else.
I think your position is just too radical here.
Ultimately all science has to eventually be used for prediction or it is useless except for aesthetic purposes. However, I do sympathize with what (I think) your main point was before, that prediction is no measure of a theory if the "theory" is just curve-fitting (it is, of course, a measure of the utility of the curve or equation that the data was fit to). That is really just common sense, though, so you may have meant something else.
This is a LessWrong idea two: play the why game, keep asking "why" all the way down. Can't find the post on this though :/
This is just a manifestation of the general fact that it is impossible to specify a hypothetical fully without telling the entire story of how things got that way from the dawn of time. Speaking of hypotheticals is thus inherently loose. There is no way to avoid fallacies in most such exercises. Feigning rigor by calling specific cases "fallacies" is pretention.
It isn't just difficult to avoid these errors; it's impossible, and relegates the exercise to the merely cautiously suggestive, not a central method of philosophy.