The first half of that video was Peterson at his best, in his field of expertise. I actually agreed with almost everything he said, and what he said reflected the literature in a fair way. The study he was privy to on cognitive ability and success sounded interesting. Second half of the video was a bit iffy and he again shows his biases when he goes off the rails and fails to take context into consideration, and is very loose with his definitions and stats.
I think we can investigate the topic, including the video, by going through the points you listed.
- IQ is the best measurement in social sciences.
A very good case could be made for this, but it depends on which parametres we use. Social sciences and qualitative reserach are generally harder to quantify in a valid way because they deal with the human psyche, subjective measures and sociological issues. In relations to other psychometric tests, IQ testing is certainly one the more valid and proven ones. There are a few other standardised questionnaires like
The Hamilton Rating Scale for Depression (HAM-D) (
1), which most agree is reliable, especially after a few revisitions (
2), and the quality of life questionnaire;
Short Form 36 (SF-36), which have shown a high validity and reliability across the board (
3,
4,
5). They aren't perfect though, none of the tests are.
There is a lot of debate about what constitutes IQ, the reliability of IQ tests, which factors contribute to IQ and how much it itself contributes to performance, although there is no doubt that it does. The problem with psychometric testing for cognitive ability is that cognition, and even problem solving, is not necessarily always the same as what you can test for on an IQ test. As Peterson himself says at 6:43;
"Then we didn't know that the factor that we had found, was the same factor as IQ. And we still haven't figured out if that was the case". There's also standard deviations, which can scew results, and that one IQ test might slightly differ from another. This is not to mention that they only test a certain parts of intelligence, mainly problem solving, math, puzzles, memory and vocabulary, but excludes emotional/social, musical, motoric and spatial intelligence.
The argument that IQ is
purely genetic is highly disputed, and does not seem to be the case. Before we go into a few smaller examples, let's talk about the
Flynn Effect which is widely recognised as a legitimate phenomenon (
6). Psychologists James Flynn, based on emperical data, showed that from 1932 to 1978 the average IQ rose almost 14 points, meaning approximately 3 points per decade. Flynn concluded that this change was due to societal changes, meaning that IQ has epigenetic components. Other studies examining IQ changes over a few years on the same person, especially in children and adolescence, has shown that IQ can change over time, and that environmental factors can impact that change (
7,
8). There is
no doubt that genetics matter in regards to your IQ, but it doesn't seem to be the only factor.
Interestingly a new study this year from
PNAS, which is one of the most respected journals in the world, showed that the Flynn Effect is reversing and presents evidence that this is caused by changes in our environment and society (
9). People are getting "dumber" (at least IQ wise).
- IQ is the greatest predictor of success.
Well, it is definitely one of them, but it's not exactly clear if it is the most important (
10). Most of the literature puts the factors for succes down into three categories.
- Cognitive ability and IQ
- Personality and social skills
- Drive
Most points to IQ/cognitive ability having an influence on whether or not someone is successful, but it being the most important factor is not exactly known. It is commonly said that that the higher skill job, the more IQ matters, but this again is debateable (
10). A lot of research seems to suggest that personality, especially traits like conscientiousness, extraversion and openmindedness, are more important for overall success in the workplace and personal life. This is in regards to grades and achievements (
11), lifetime earnings (
12) and various other outcomes of success (
13). Some evidence has suggested that, when coming from a lower socioeconomical status (SES), intelligence might be the more important equalizer, but this is incredibly complex (
14).
So no, It doesn't seem like it's fair to conclude that IQ is the most important predictor, based on the evidence avaliable.
- The military says that people with an IQ under 83 are ineligible (i.e. useless).
I tried to look for the source of this claim and all I could find was an article on wikipedia:
https://en.m.wikipedia.org/wiki/Intelligence_quotient, which links to this article by a single author:
https://www1.udel.edu/educ/gottfredson/reprints/2004socialconsequences.pdf. There's no citations, or sources for the claim.
The military doesn't use standard IQ tests, they use the Armed Services Vocational Aptitude Battery (ASVAB) test and the requirements vary (
15). I did however find this written in the US military code (
16);
"10 USC §520:
(a)
The number of persons originally enlisted or inducted to serve on active duty (other than active duty for training) in any armed force during any fiscal year whose score on the Armed Forces Qualification Test is at or above the tenth percentile and below the thirty-first percentile may not exceed 20 percent of the total number of persons originally enlisted or inducted to serve on active duty (other than active duty for training) in such armed force during such fiscal year."
Turns out that in 1997, 12.000 individuals from age 16-23 was given the ASVAB test and their results set the standard for the population average (
17). This means that new recruits have to be at or above 10% of that set average. So, depending on how well the ASVAB correlates to other IQ tests, and what their inclusion criteria were in 1997, I'd say that the claim is somewhat factual. I think that if you are going to be handling firearms and be responsible for other peoples lives It's probably a good thing that you are at least somewhat smarter than the bottom 10% of the population. Being in the military and holding a regular job is two distinctive things though, with different responsibilities.
I wont address the point about unruly children correlating to criminal behavior later in life, because I simply don't have time right now (I might come back and edit it in), but as far as I know that statement is largely supported by data, although I'm sure some context is being left out if I know Jordan Peterson. Especially the claim that "we can't do anything" is something that needs to be researched. My bullshit meter is going off a tiny bit.
Now addressing the larger points in the video, that Peterson feels like we should all be extremely scared of the fact that 10% of the population has an IQ of less than 85, because the military wont take in people with in IQ under 85. We've already examined how the military argumentation is a bit shaky, and the claim fails to take other things into consideration. It is definitely true that in the context of a society that is growing rapidly in the evolution of technology, innovation and high skill jobs, some people will have a harder time adjusting. However, the current unemployment numbers doesn't show a trend in that direction. Rather it shows that what really dictated job affluence are politics and economics, with the financial crash being the single most important factor in unemployment during the last 10 years (
18). The other part of the coin is that technology is being "dumbed down" so it is easier to implement for workers in manual labor jobs, and consumers as a whole. I suspect that in part this has something to do with the reverse Flynn Effect mentioned earlier.