We're applying higher criteria for genius. But are we really?
I think this is more likely than not, but I couldn't quantify it. I think it's more likely for the simple reason that what earlier geniuses (like von Neumann etc.) did has already been done. To me, that implies the genius bar has been raised, in absolute terms, at least in the hard sciences and math.
The average has moved up, but the variance has shrunk. But this would have to be implausibly extreme shrinkage,
Agree.
The modern culture is making common folks smarter, but it drags geniuses down. I believe there might be some truth to this. The pop culture everyone's supposed to follow, however trashy, has gotten more demanding mentally, but true intellectual pursuits have lost a lot of status compared to the past. Still, such effects can't explain the severity of the effect --
Agree. It's hard for me to imagine many geniuses getting derailed just by trash TV and ostracism.
The IQ scores say a lot about people who are average or below average, but not much about smart people. This seems like the most plausible option to me, and the only one compatible with evidence.
I believe IQ still correlates positively with performance among very high-achievers, just not as well as for normal people. The biggest factor here might be touched on in your second paragraph:
Moreover, it assumes that people whose intellects stand out as strikingly brilliant are drawn -- as a necessary condition, and not too far from sufficient -- from the pool of those whose general intelligence is exceptionally high.
I would bet that the standouts you're talking about would have higher average IQ, but would not actually be 'exceptionally' high, because IQ doesn't correlate that well with success. Also, many of the geniuses we're thinking of would probably be specialists, and it's harder to track specialized performance with the (relatively) generalist metric of IQ. If the IQ threshold for genius is lower than you think, an upward shift in the mean makes less difference. (Of course it can't explain the effect away entirely; something else is happening. But it could be a part.)
cupholder:
I think it's more likely for the simple reason that what earlier geniuses (like von Neumann etc.) did has already been done. To me, that implies the genius bar has been raised, in absolute terms, at least in the hard sciences and math.
That could well be the case. However, it fails to explain the lack of apparent genius at lower educational stages. For example, if you look at a 30 year period in the second half of the 20th century, the standard primary and high school math programs probably didn't change dramatically during this time, and they...
Edit: Q&A is now closed. Thanks to everyone for participating, and thanks very much to Harpending and Cochran for their responses.
In response to Kaj's review, Henry Harpending and Gregory Cochran, the authors of the The 10,000 Year Explosion, have agreed to a Q&A session with the Less Wrong community.
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