Optimal IQ: A Speculative Model

How we profit from IQ is frequently talked about in IQ societies. And the foregone conclusion: the higher the better. However, turns out there’s a cost associated with higher IQ, one put forth in a recent paper[1] indicating the good of high intelligence; more opportunities, higher self–awareness, etc and the more elusive bad or dark side to higher IQ; imbalances (mental and physical), debilitation, etc. In other words, there is a cost associated with IQ increase beyond some as yet, unknown value. Now, optimality, as we all know, is not necessarily being on top of the heap or at a maximum. Take an aspirin, it will get rid of a headache. Take a bottle of aspirin and you’ll be in the ER getting your stomach pumped. Even money—turns out you don’t want to make too much—has an optimal value being about $95,000.00 US dollars per year in the long run, that is, if one wants to be happy— optimally of course.

Too, to determine optimality, as we all have learned, requires in the simplest sense the cost of something as well as its profit. We know the profit of high IQ, that’s been talked about and studied to death. But what about its cost? In this rather I say, speculative, hypothetical, and assumed model, I will consider only the psycho–social cost—that being, a measure of the psychological and social disturbances or disruptions associated with any “positive” change in IQ beyond the norm and especially with high and ultra high IQ in particular. In their paper, Ruth I. Karpinski, et al. considered a sample population of Mensa members (n = 3217) with IQs at or above 130 IQ (sd = 15). These members were then provided a quesstionerre to determine prevlance of diagnosed and suspected disease, both physiological and psychological/social. Turns out, the Mensa members had psychological/social disorders at roughly four times the national (US) rate. Normal IQ (US = 98 IQ), for instance, had mood disorders and anxieties in 9.5% and 10.9% consecutively of the total population.

Compare that with a 36.6% and 37.3% for Mensa members consecutively. The differences are indeed staggering. Food for thought!—how could one construct a cost/benefit analysis of IQ increase to ferret out what might be considered optimal intelligence? Suppose we change those pesky percentages above to proportions. Of course, that will scale them from zero to one inclusive. Now, as a sort of null hypothesis we might consider absolutely no cost associated with IQ increase, in other words, supposing there exists no relationship between IQ and mental or social health. We might set a sort of psychological/social cost or score to zero for instance. Thus, that cost, subtracted from one and multiplied by IQ would certainly yield one’s IQ score, e.g.

IQ (1 - 0)

there being in this case no loss of mental or social function due to IQ increase. However, this is not the case. There is a loss, for the general population, a mean loss of 10.2% or 0.102 on our [0,1] scale and for the Mensa population a mean loss of 36.95% or 0.370. Reconsidering the formula above, one might surmise or deduce a generalization of this as our said score, that is, as a sort of weighted IQ. Of course, the relationship in this formula cannot be linear, as there’s benefit to having a low IQ, less mood and anxiety disorders as compared with the Mensa population having about a high IQ of about or average 140 ± 5. So, what is it then, this score? Well, how about a simple relation between IQ and psychological/social cost, that is, an SPE or (Social/Psychological Equanimity score) to determine just what we are searching for, optimal IQ. Let’s, for argument’s sake, set

SPE = IQ (1 - p)

where p is simply the average proportion of mood and anxiety disorders as stated above in the considered population, normal and Mensa were my only given data points, and IQ is simply the average IQ of each of those said populations. The benefit then becomes an expression of one minus the cost, that is, (1 - p), that being a sort of weighted IQ score or SPE as we called it. Obviously, as mentioned, normal intelligence disrupts the mental and social life very little while superior intelligence, 130 IQ or greater exacts a wholly increased cost. Using these IQs as my endpoints, IQ = 98 for the normal US population and IQ = 135, 140, and 145 for the Mensa, I graphed IQ versus SPE and determined the following extracting the inflection points on the various graphs... see Figure 1 below.

Figure 1.

Of course, higher SPE reflects a better quality of life given a particular IQ, e.g., for Mensa average IQ of 140 (best guess), the optimal IQ for an individual to possess in this society is IQ~120. That is, an IQ of 120 maximizes one’s SPE score thus achieving the greatest possible benefit of opportunity and self–awareness with the least impact to mental health and welfare. Too, with higher and lower Mensa averages that optimum changes, achieving its greatest value at IQ 145 and ranging as it were from a lower bound of 111 IQ to a theoretical upper bound of 128 IQ. Most professional mean IQs exist in this said range from graduating college, 115 IQ, to the profession of doctors and lawyers, 125 IQ. If anything, interesting to say the least.

Conclusion:

Higher IQ above the mean (IQ = 98) brings more opportunities, higher self–awareness, etc. Too, up to a point, increase in IQ actually seems to bring greater mental and physical equanimity, that is, greater SPE scores reaching a maximum around the 111 IQ, 119 IQ and 128 IQ marks for considered Mensa average IQs of 135, 140 and 145 which, I suspect, 140 to be close to the true mean IQ of Mensa members and the sample in particular. And then, rather tragically, SPE scores drop off drastically with increase in IQ (NOTE: I suspect these drop off very quickly at the given endpoints but any extrapolation is of course, hypothetical, though nonlinearly fitting), bottoming out at our self imposed limits of the considered US average and 200 IQs. At the very least, that is, even with a shoddy model of sorts, we can begin to objectify optimal IQ and get away from all the anecdotal and many considerations that tend to place optimal IQ in a subjective light generally making it unreliable and thus of questionable value.

1. Ruth I. Karpinski, Audrey M. Kinase Kolb, Nicole A. Tetreault, Thomas B. Borowski. (2018). High intelligence: A risk factor for psychological and physiological overexcitabilities. Intelligence ISSN 0160-2896 , 66, 8-23.

Kenneth Myers