(At this point, I fear that I must recurse into a subsequence; but if all goes as planned, it really will be short.)
I once lent Xiaoguang "Mike" Li my copy of "Probability Theory: The Logic of Science". Mike Li read some of it, and then came back and said:
"Wow... it's like Jaynes is a thousand-year-old vampire."
Then Mike said, "No, wait, let me explain that—" and I said, "No, I know exactly what you mean." It's a convention in fantasy literature that the older a vampire gets, the more powerful they become.
I'd enjoyed math proofs before I encountered Jaynes. But E.T. Jaynes was the first time I picked up a sense of formidability from mathematical arguments. Maybe because Jaynes was lining up "paradoxes" that had been used to object to Bayesianism, and then blasting them to pieces with overwhelming firepower—power being used to overcome others. Or maybe the sense of formidability came from Jaynes not treating his math as a game of aesthetics; Jaynes cared about probability theory, it was bound up with other considerations that mattered, to him and to me too.
For whatever reason, the sense I get of Jaynes is one of terrifying swift perfection—something that would arrive at the correct answer by the shortest possible route, tearing all surrounding mistakes to shreds in the same motion. Of course, when you write a book, you get a chance to show only your best side. But still.
It spoke well of Mike Li that he was able to sense the aura of formidability surrounding Jaynes. It's a general rule, I've observed, that you can't discriminate between levels too far above your own. E.g., someone once earnestly told me that I was really bright, and "ought to go to college". Maybe anything more than around one standard deviation above you starts to blur together, though that's just a cool-sounding wild guess.
So, having heard Mike Li compare Jaynes to a thousand-year-old vampire, one question immediately popped into my mind:
"Do you get the same sense off me?" I asked.
Mike shook his head. "Sorry," he said, sounding somewhat awkward, "it's just that Jaynes is..."
"No, I know," I said. I hadn't thought I'd reached Jaynes's level. I'd only been curious about how I came across to other people.
I aspire to Jaynes's level. I aspire to become as much the master of Artificial Intelligence / reflectivity, as Jaynes was master of Bayesian probability theory. I can even plead that the art I'm trying to master is more difficult than Jaynes's, making a mockery of deference. Even so, and embarrassingly, there is no art of which I am as much the master now, as Jaynes was of probability theory.
This is not, necessarily, to place myself beneath Jaynes as a person—to say that Jaynes had a magical aura of destiny, and I don't.
Rather I recognize in Jaynes a level of expertise, of sheer formidability, which I have not yet achieved. I can argue forcefully in my chosen subject, but that is not the same as writing out the equations and saying: DONE.
For so long as I have not yet achieved that level, I must acknowledge the possibility that I can never achieve it, that my native talent is not sufficient. When Marcello Herreshoff had known me for long enough, I asked him if he knew of anyone who struck him as substantially more natively intelligent than myself. Marcello thought for a moment and said "John Conway—I met him at a summer math camp." Darn, I thought, he thought of someone, and worse, it's some ultra-famous old guy I can't grab. I inquired how Marcello had arrived at the judgment. Marcello said, "He just struck me as having a tremendous amount of mental horsepower," and started to explain a math problem he'd had a chance to work on with Conway.
Not what I wanted to hear.
Perhaps, relative to Marcello's experience of Conway and his experience of me, I haven't had a chance to show off on any subject that I've mastered as thoroughly as Conway had mastered his many fields of mathematics.
Or it might be that Conway's brain is specialized off in a different direction from mine, and that I could never approach Conway's level on math, yet Conway wouldn't do so well on AI research.
Or...
...or I'm strictly dumber than Conway, dominated by him along all dimensions. Maybe, if I could find a young proto-Conway and tell them the basics, they would blaze right past me, solve the problems that have weighed on me for years, and zip off to places I can't follow.
Is it damaging to my ego to confess that last possibility? Yes. It would be futile to deny that.
Have I really accepted that awful possibility, or am I only pretending to myself to have accepted it? Here I will say: "No, I think I have accepted it." Why do I dare give myself so much credit? Because I've invested specific effort into that awful possibility. I am blogging here for many reasons, but a major one is the vision of some younger mind reading these words and zipping off past me. It might happen, it might not.
Or sadder: Maybe I just wasted too much time on setting up the resources to support me, instead of studying math full-time through my whole youth; or I wasted too much youth on non-mathy ideas. And this choice, my past, is irrevocable. I'll hit a brick wall at 40, and there won't be anything left but to pass on the resources to another mind with the potential I wasted, still young enough to learn. So to save them time, I should leave a trail to my successes, and post warning signs on my mistakes.
Such specific efforts predicated on an ego-damaging possibility—that's the only kind of humility that seems real enough for me to dare credit myself. Or giving up my precious theories, when I realized that they didn't meet the standard Jaynes had shown me—that was hard, and it was real. Modest demeanors are cheap. Humble admissions of doubt are cheap. I've known too many people who, presented with a counterargument, say "I am but a fallible mortal, of course I could be wrong" and then go on to do exactly what they planned to do previously.
You'll note that I don't try to modestly say anything like, "Well, I may not be as brilliant as Jaynes or Conway, but that doesn't mean I can't do important things in my chosen field."
Because I do know... that's not how it works.
I did not say that non-reductionism is absurd. I said that "recognizing the absurdity of all other proposed hypotheses is another way of coming about the correct beliefs".
Nonetheless, I do think that non-reductionism is absurd. I cannot imagine a universe which is not reductionistic.
One formulation of reductionism is that natural laws can be ordered in a hierarchy, with the higher-level laws being predictable from, or reducible to, the lower ones. So emergentism, in the cognate sense, not working would be that stack of laws failing to collapse down to the lowest level.
There's two claims there: one contentious, one not. That there are multiply-realisable, substrate-independent higher-level laws is not contentious. For instance, wave equations have the same form for water waves, sound waves and so on. The contentious claim is that this is ipso facto top-down causation. Substrate-independent laws are still reducible to substrates, because they are predictable from the behaviour of their substrates.
I don't see how that refutes the above at all. For one thing, Laughlin and Ellis do have detailed examples of emergent laws (in their rather weak sense of "emergent"). For another, they are not calling on emergence itself as doing any explaining. "Emergence isn't explanatory" doesn't refute "emergence is true". For a third, I don't see any absurdity here. I see a one-word-must-have-one-meaning assumption that is clouding the issue. But where a problem is so fuzzilly defined that it is hard even to identify the "sides", then one can't say that one side is "absurd".
Neither are supposed to make predictions. Each can be considered a methodology for finding laws, and it is the laws that do the predicting. Each can also be seen as a meta-level summary fo the laws so far found.
EY can't do that for MWI either. Maybe it isn't all about prediction.
That's robustly true. Genetic code has to be interpreted by a cellular environment. There are no self-decoding codes.
Reudctionism is an approach that can succeed or fail. It isn't true apriori. If reductionism failed, would you say that we should not even contemplate non-reductionism? Isn't that a bit like eEinstein's stubborn opposition to QM?
I suppose you mean that the reductionistic explanation isn't always the most complete explanation...well everything exists in a context.
There is no apriori guarantee that such an explanation will be complete.
That isn't the emergentist claim at all.
Why? Because you described them as "laws of physics"? An emergentist wouldn't. Your objections seem to assume that some kind of reductionism+determinism combination is true ITFP. That's just gainsaying the emergentist claim.
If there is top-down causation, then its laws must be couched in terms of lower-level AND higher-level properties. And are therefore not reductionistic. You seem to be tacitly assuming that there are no higher-level properties.
Cross-level laws aren't "laws of physics". Emergentists may need to assume that microphysical laws have "elbow room", in order to avoid overdetermination, but that isn't obviously wrong or absurd.
As it happens, no-one does. That objections was made in the most upvoted response to his article.
Can you predict qualia from brain-states?
Mechanisms have to break down into their components because they are built up from components. And emergentists would insist that that does not generalise.
Or as a hint about how to go about understanding them.
That's not what E-ism says at all.
That's an outcome you would get with common or garden indeterminism. Again: reductionism is NOT determinism.
What's supposed to be absurd there? Top-down causation, or top-down causation that only applies to DNA?
The arguments for emergence tend not be good. Neither are the arguments against. A dippsute about a poorly-defined distinction wit poor arguments on both sides isn't a dispute where one side is "absurd".