To start with, some people insist that intelligence doesn’t exist; they are, I suspect, the best evidence for their case. Some people and some groups are obviously smarter than others. It’s daily experience.
Then other people, also imbeciles, say that environment accounts for all difference in IQ: It’s all in how you are raised. The idea would embarrass a hamster.
Consider. Chuck Gauss, usually regarded as one of the world’s three greatest mathematicians, was born to a poor family of peasant stock in Germany. So were tens of thousands of other boys, all of whom, on the environmental theory, should have been among the world’s three greatest mathematicians. You see the problem. Newton, another of the three, was born into a family of small farmers. (The farms were small, not the farmers.) So was half of England. No method of fluxions from the rest.
OK, that’s easy, but then I start getting confused. There is, for example, the correlation between size of brain and intelligence. Bigger is better, we think. It makes a certain intuitive sense. A big one should be stronger than a small one. But:
Philippe Rushton, a professor at the University of Western Ontario, argues that blacks have a mean IQ fifteen points below that of whites because they have a brain volume less by 100 cubic centimeters; whites have an IQ about five points lower than that of East Asians because of a similar but lesser difference in the weight of the brain. (Rushton’s book, Race, Evolution, and Behavior, is worth reading. Amazon has it.) Others have argued that women, whose brains are a tad smaller than those of men, are a tad less intelligent. All of this tracks observable results.
Rushton of course is charged with racism. If so, he is a white racist who argues that East Asians are superior to whites, which injects a certain political opacity. The confusion vanishes if you regard him as a scientist studying brains.
Now, I don’t deny the correlation but, being as I am intellectually barefoot, I’m puzzled by this brain business. In biology books, one sees drawings that purport to illustrate the evolution of intelligence. For instance, you might see running across the page some ancient and by implication witless reptile (though, hey, maybe it read Kant) with a tiny brain, followed by a small ancestral mammal and then by primitive primates, then chimpanzees (with brains of 420 grams ), and then Man (sort of 1350 grams). The reader is invited to conclude that intelligence tracks the size of the brain in an orderly and evolutionary manner.
But it seems to me that one could arrange the evidence otherwise. You go up the sleepy chain to chimps, which are perhaps smart enough to poke at low-hanging fruit with a stick. Then you come to Man, who does npn junctions and Lebesgue integrals and Dostoevsky. Then, continuing up the scale of brain volume, you find porpoises, with brains larger than ours (1550 grams) but quite dim, and then sperm whales, with gynormous brains (7800 grams) but no discernible theoretical inclinations whatever. Man looks less like the culmination of a comprehensible progression than a wild and inexplicable anomaly.
Am I missing something? (“Yes! A brain!” I hear wits shouting.)
At this point the partisans of IQ sometimes say that what matters for intelligence is not the absolute size of the brain but the size of the brain divided by body weight. Why? (Probably because it produces a straight line on a graph, but never mind.) On this reasoning, a man of 120 pounds with a brain of a given size should be twice as smart as a man of 240 pounds with a brain of the same size.
I asked an IQist about this. He responded that what counts is not the weight of an individual, but the average for the species. Oh. My intelligence is determined by how much other people weigh. Why didn’t I think of that?
I don’t get it. Some parts of the brain are used for thinking, and others are not. For example, people do not think with their brain stems, except perhaps news anchors. So why is intelligence not related to the absolute size of the thinking parts, independent of bodily weight? A computer has the same power whether mounted on an aircraft carrier or a little red wagon.
A book much in esteem among IQists is IQ and the Wealth of Nations, by Richard Lynn and Tatu Vanhanen. The authors attempt to determine the mean IQ of different countries and correlate the results with national income. It is an interesting idea and seems more or less to work, sort of, mostly, when it does. I suspect they should have subtitled the book “A Study in Too Many Undeterminable Variables,” but who am I? (Since the book costs $93 at Amazon, I presume that the authors want to keep their findings secret.)
Here as elsewhere in IQ stuff you can get into a lot of statistics and Gaussians and funny distributions, which enshroud the matter is a cloud of awe. However, it occurs to me that slick mathematics applied to soft data yield slick, soft results that would be dangerous if left on a sidewalk.
Anyway, the authors assert that Equatorial Guineans have a mean IQ of 59, as for all I know they may. There is also in the lore of IQ Marilyn vos Savant, said to have had an IQ measured at 228. Call the numbers 60 and 230 for arithmetical convenience. That gives a difference of 170 which, at 100 cc per fifteen IQ points, comes to 11.33 times 100cc giving her a head with over 1100 cc more volume than that of the Equatorial Guinean. She would need a chain hoist to stand up, I should think. Or else the Guineans are nanocephalic.
On a mailing list of IQ folk, to which I belonged, mention was made of Ms. vos Savant, whereupon a member posted that he had heard that she “stabilized at 180.” Now, a post on a list is not canonical. Still, it is interesting that no one demurred. If she stabilized at 180, then the IQ test was accurate only to within 48 points. Helluva test, that. And if both numbers were correct, then her head must have shrunk visibly as she subsided to 180, no doubt alarming her friends. (I think the elasto-cranial theory of intelligence is brilliant.)
I’m being a smart-ass. Still, a lot of this stuff seems murkier than it is presented as being, more immobilized by ideological entrenchment and true belief. Wotthehell.
Then there is what is called the Flynn Effect, (here or more elaborately, here) associated with James R. Flynn, who noticed that IQ was rising by three points per decade. It seems we are getting smarter, fast. Unless of course we aren’t. (The increase doesn’t show up in the mean IQ because it is pegged at 100.)
Now, either the increase is real—that is, intelligence is rising rapidly—or it is an artifact of testing. If it is real, then (as everybody and his pet goat must notice) in 1945 the mean IQ of white Americans was 85, a full standard deviation below the mean today and exactly the mean IQ today attributed to American blacks. This means that a mean IQ of 85 is sufficient to manage the vast techno-industrial undertakings of WWII, to produce radar and Doppler-prox fuses and Bletchley Park.
On the other hand, if the increase is not real, but an artifact of testing, then IQ tests are not accurate to within a standard deviation over fifty years in a single culture; this might lead one to question their application across very different cultures. Unless one were an IQist.
Recently, Flynn has said that IQ is no longer increasing, that it rose because people were exposed to a more demanding intellectual environment as time went on. You know, computers and Game Boys and such. Fine. But this means that the environmental component of IQ has increased rapidly, specifically by fifteen points, and, indeed, one hundred percent of the difference between whites in 1945 and those of today is of environmental provenance. But then…but then….
I don’t get it. I guess I confuse easily because I came down out of the mountains of West Virginia with no shoes and twelve toes. It’s why we use base-12 arithmetic in Wheeling.