As a Canadian with an IQ blog, I have a patriotic duty to report on this latest study showing that on the latest revision of the Wecshler adult intelligence scale, the average American has an overall IQ of 100 (by definition) while Canadians have a mean of 104.5 (hat tip to scholar Emil OW Kirke Gaard on twitter). Assuming both countries were tested around the same time and thus no Flynn effect corrections are required, that’s a pretty fascinating result. While a 5 point difference may sound trivial, a radical theory proposed that the human mind operates in parallel, so a 5 point difference in IQ causes a doubling in problem solving speed. If this theory is scientifically correct, Canadians are twice as smart as Americans.
The concept of intelligence doubling every 5 IQ points is extremely confusing for people because the fastest reaction times humanly possible are not even twice as quick as the average reaction time, so how the heck can the smartest people be tens of thousands of times smarter than average people? But smarter people don’t just have faster minds, the have greater working memory capacity, and each one unit increase in working memory should be regarded as increase in mental bandwidth. The speed with which water can fill a tank is a not just a function of how fast it’s traveling, but how wide the water hose is. Smarter people don’t just have faster nerve conduction speeds, they also have bigger brains that can hold more information simultaneously, but unless you have an IQ above 150 and a background in computer science to boot, don’t even try to understand what I’m talking about, because you don’t have the speed or parallel processing to cope with a concept this complex and abstract.
Back to Canadians being twice as smart as Americans. I think a good example of this was that Canada had the wisdom to oppose the Iraq war, which in retrospect has turned out to be a mistake. Another example is that even students at Harvard (America’s most prestigious university) can’t tell you the capital of Canada.
How does one not know the capital of one of only two countries that border your own, despite having the finest education money can buy? I guarantee that you could walk into any Canadian university and the vast majority of students would know America’s capital. Of course in fairness, Canadians pay far more attention to America than Americans pay to us because America is arguably still the World’s sole superpower.
So if Canadians are so smart, why aren’t we the leading superpower? It’s partly because our population is smaller and our IQ’s are much less variable, so America should have far more incredibly brilliant people than Canada does (the Canadian IQ standard deviation is only 13.4 compared to the American SD of 15). Assuming an idealized Gaussian distribution, the smartest American has an IQ of 187, while the smartest Canadian has an IQ of 177. So while the average Canadian might be twice as smart as the average American, the smartest American might have quadruple the intelligence of the smartest Canadian.
Brain Size 
Hmmm…
If fully corrected for race I doubt whether there would a significant difference between the US and Canadian population – although the USA does attract ultra-high IQ immigration (eg the brain drain in science and technology) in a way that Canada does not.
But more fundamentally, I would say the idea that people with an IQ of 105 are ‘twice’ as intelligent as those of IQ 100 is self-refuting, a reductio ad absurdum – because in real life you cannot distinguish the two. I find it inconceivable, just plain wrong, that there is a doubling/ halving of problem solving speed (if ‘problem’ had any real meaning) – which would presumably be intended as a proxy for cognitive processing speed.
On the basis of reaction times the values would seem to be that the highest intelligence is reached at an RT of about 150 ms, which would imply that half that intelligence is at about 300 ms.
To give precise IQ numbers to these RT values would require a proper sampling procedure and measuring the relationship between RT and IQ – but I *very roughly* estimated doubling or intelligence/ processing speed corresponds to about *three* standard deviations of IQ difference (i.e. between IQ 85 and IQ 130) or more:
http://iqpersonalitygenius.blogspot.co.uk/2013/02/the-ordinal-scale-of-iq-could-be.html
This feels to me much more in line with what I would perceive in real life – certainly an IQ difference of 85-130 is pretty easy to detect at a one to one level (unlike the difference between 100-105) – unless you rally don’t want to admit it is really there.
No one’s disputing that the smartest people are less than twice as fast as normal people on elementary cognitive tasks. The promethean who came up with the doubling hypothesis was well aware of this as he was a huge chronometrics aficionado.
However because the human mind operates in parallel, & because smarter people not only have faster reaction times, they also have more parallel processing ability, he argued that a doubling in reaction speed resulted in orders of magnitude differences in complex reasoning speed.
You’ve also written about how g is not simply about reaction time, but also about working memory, so you can imagine how being good on both variables might have a multiplier effect.
It’s a fun theory but it could be nonsense. However if you walk into say a university math class where all the students have IQ’s from say 120-140, it’s quite evident that the brightest student grasps what the professor is talking about ten times faster than the dullest. Whether this is because of a fundamental difference in intelligence or because of difference in prior learning, I’m not sure.
@Pp “However if you walk into say a university math class where all the students have IQ’s from say 120-140, it’s quite evident that the brightest student grasps what the professor is talking about ten times faster than the dullest.”
If that is true, it may be specific to maths. Something similar, or even more extreme, could be found in music. But in more general discourse, I don’t think that observation is correct.
I don’t know enough about music to comment, but the doubling hypothesis seems to work well for math & spatial ability, but sounds quite absurd when you talk about verbal ability. It’s not as though vocabulary doubles every 5 verbal IQ points, that would be EXTREMELY noticeable.
I need to find the Promethean’s original article to gain a better understanding of exactly what he was saying and why.
I now realise you aren’t joking with this… I realise this Promethean impressed you but you lend too much weight in your writings too his words, which I am sure are not backed up by valid scientific testing.
If 5 IQ points was a doubling of problem solving ability then it would seem likely that at the limits of human intelligence only the very brightest could make progress (as they have vastly more brain firepower) so the IQs 180 and up. What we find however is that the average Nobel winner for science is maybe 3 sds above the mean – bright but in your scale 7 doublings or 128x less intelligent than a 180. I don’t think it is feasible that conscientiousness could make up a difference of that magnitude.
So I would give this concept up unless you have very good evidence.
I agree I need more evidence, but,
If 5 IQ points was a doubling of problem solving ability then it would seem likely that at the limits of human intelligence only the very brightest could make progress (as they have vastly more brain firepower) so the IQs 180 and up. What we find however is that the average Nobel winner for science is maybe 3 sds above the mean – bright but in your scale 7 doublings or 128x less intelligent than a 180. I don’t think it is feasible that conscientiousness could make up a difference of that magnitude.
Money is something that doubles every few percentiles. The richest people are thousands of times richer than most of us. Doesn’t mean the happiest people are all billionaires…other factors can still make up huge differences in magnitude.
Analogously, the best scholars don’t need to all be super-brains.