You accuse lukeprog of being misleading in taking a quote from a mere "librarian", and as we all know, a librarian is a harmless drudge who just shelves books
I really can't think of a polite way to say this, so:
Bullshit.
I wasn't accusing Luke of anything; I was disagreeing with him. Disagreement is not accusation. When I want to make an accusation, I will make an accusation, like this one: You have mischaracterized what I wrote, and made totally false insinuations about my opinions and attitudes, and I have to say I'm pretty shocked to see someone as generally excellent as you behaving in such a way.
I do not think, and I did not say, and I had not the slightest intention of implying, that "a librarian is a harmless drudge who just shelves books".
Allow me to remind you how Luke's comment begins. The boldface emphasis is mine.
We also know many famous examples of scientists just completely making up their pessimism, for example about the impossibility of human heavier-than-air flight.
This isn't what you asked for, but I might as well enumerate a few of these examples, for everyone's benefit. For the field of AI research:
Taube was, despite his many excellent qualities, not a scientist as that term is generally understood, and he was, despite his many excellent qualities, not working in "the field of AI research".
(Yes, I know the Wikipedia page says he was "a true innovator in the field of science". Reading what it says he did, though, I really can't see that what he did was science. For the avoidance of doubt, and in the probably overoptimistic hope that saying this will stop you pulling the same what-a-snob-this-person-is move as you already did above, I don't think that "not science" is in any way the same sort of thing as "not valuable" or "not important" or "not difficult". What the creators of (say) the Firefox web browser did was important and valuable and difficult, but happens not to be science. What Beethoven did was important and valuable and difficult, but happens not to be science. What Martin Luther King did was important and valuable and difficult, but happens not to be science.)
Pointing this out doesn't mean I think there's anything wrong with being a librarian. When I said "a librarian is a fine thing to be", I meant it. (And, for the avoidance of doubt, it is my opinion both when "librarian" means "someone who shelves books in a library" and when it means "a world-class expert on organizing information in catalogues".)
Now, having said all that, I should add that you are quite right about one thing: when I said that Taube was neither a computer expert nor a philosopher, I was oversimplifying. (Not least because I hadn't looked deeply into Taube's career.) He was an important innovator in the use of punched cards for document indexing, which is quite a bit like being a computer expert; and he was a PhD in philosophy, which is quite a bit like being a philosopher. None the less, I stand by what I said: neither being a world-class expert in document indexing, nor knowing a lot about punched-card reading machinery, nor being a PhD in philosophy, seems to me to be the kind of expertise that makes it particularly startling if one's wrong about whether machines can play chess.
(And, once again, for the avoidance of doubt, I am not in the least trying to belittle his expertise and creativity. I just don't see that they were the kind of expertise and creativity that make it startling for someone to be wrong about the possibilities of computer chess-playing.)
[EDITED to clarify a bit of wording and add some emphasis. ... And again, later, to add a missing negative; oops. Also, while I'm here, two other remarks. 1: I regret the confrontational tone this exchange has taken; but I don't see any way I could have responded sufficiently forcefully to the accusations levelled at me without perpetuating it. 2: I see a lot of downvotes are flying around in this subthread. For the record, I haven't cast any.]
In an erratum to my previous post on Pascalian wagers, it has been plausibly argued to me that all the roads to nuclear weapons, including plutonium production from U-238, may have bottlenecked through the presence of significant amounts of Earthly U235 (apparently even the giant heap of unrefined uranium bricks in Chicago Pile 1 was, functionally, empty space with a scattering of U235 dust). If this is the case then Fermi's estimate of a "ten percent" probability of nuclear weapons may have actually been justifiable because nuclear weapons were almost impossible (at least without particle accelerators) - though it's not totally clear to me why "10%" instead of "2%" or "50%" but then I'm not Fermi.
We're all familiar with examples of correct scientific skepticism, such as about Uri Geller and hydrino theory. We also know many famous examples of scientists just completely making up their pessimism, for example about the impossibility of human heavier-than-air flight. Before this occasion I could only think offhand of one other famous example of erroneous scientific pessimism that was not in defiance of the default extrapolation of existing models, namely Lord Kelvin's careful estimate from multiple sources that the Sun was around sixty million years of age. This was wrong, but because of new physics - though you could make a case that new physics might well be expected in this case - and there was some degree of contrary evidence from geology, as I understand it - and that's not exactly the same as technological skepticism - but still. Where there are sort of two, there may be more. Can anyone name a third example of erroneous scientific pessimism whose error was, to the same degree, not something a smarter scientist could've seen coming?
I ask this with some degree of trepidation, since by most standards of reasoning essentially anything is "justifiable" if you try hard enough to find excuses and then not question them further, so I'll phrase it more carefully this way: I am looking for a case of erroneous scientific pessimism, preferably about technological impossibility or extreme difficulty, where it seems clear that the inverse case for possibility would've been weaker if carried out strictly with contemporary knowledge, after exploring points and counterpoints. (So that relaxed standards for "justifiability" will just produce even more justifiable cases for the technological possibility.) We probably should also not accept as "erroneous" any prediction of technological impossibility where it required more than, say, seventy years to get the technology.