Spatial visualization (mentally visualizing/manipulating a 3D environment: “If I tip this table it’ll slow him down and I can dive out that window.”)
Thurstone derived his Primary Mental Abilities after devising his own methods of factor analysis and applying them to IQ test results of thousands of college students.3 However, reanalysis of his results using more traditional factor analysis showed there was a single ability influencing all the tests, rather than several different ones. Basically, he’d discovered g again. This and other criticisms (for instance that he studied only college students, hardly the most representative group when it comes to general human intelligence) meant the Primary Mental Abilities weren’t that widely accepted.
Multiple intelligences returned in the 1980s via Howard Gardner, a prominent researcher who proposed that there were several modalities (types) of intelligence, and his aptly titled Theory of Multiple Intelligences, following research into brain-damaged patients who still retained certain types of intellectual abilities.4 His proposed intelligences were similar to Thurstone’s in some ways, but also included musical intelligence, and personal intelligences (ability to interact well with people, and ability to judge your own internal state).
The multiple-intelligence theory has its adherents though. Multiple intelligences are popular largely because it means everyone can potentially be intelligent, just not in the “normal” brainy geek way. This generalizability is also something it’s criticized for. If everyone is intelligent, the concept itself becomes meaningless in the scientific sense. It’s like giving everyone a medal for showing up at a school sports day; it’s nice that everyone gets to feel good, but it does defeat the point of “sport.”
So far, the evidence for the multiple-intelligence theory remains debatable. The data available is widely regarded as being yet more evidence for g or something like it, combined with personal differences and preferences. What this means is that two people who excel, one at music and one at math, aren’t actually demonstrating two different types of intelligence, but the same general intelligence applied to different types of tasks. Similarly, professional swimmers and tennis players use the same muscle groups to practice their sports; the human body doesn’t have dedicated tennis muscles. Nonetheless, a champion swimmer can’t automatically play top-level tennis. Intelligence is believed to work in similar ways.
Many argue that it is perfectly plausible to have a high g but prefer to utilize and apply it in specific ways, which would manifest as different “types” of intelligence if you look at it in a certain way. Others argue that these supposed different types of intelligence are more suggestive of personal inclinations based on background, tendencies, influences, and so on.
Current neurological evidence still favors the existence of g and the fluid/crystallized set-up. Intelligence in the brain is believed to be due to the way the brain is arranged to organize and coordinate the various types of information, rather than a separate system for each one. This will be covered in more detail later in this chapter.
We all direct our intelligence in certain ways and directions, whether due to preference, upbringing, environment or some underlying bias imparted by subtle neurological properties. This is why you get supposedly very smart people doing things we’d consider foolish; it’s not that they aren’t clever enough to know better, it’s that they’re too focused elsewhere to care. On the plus side, this probably means it’s OK to laugh at them, as they’ll be too distracted to notice.
Empty vessels make the most noise
(Why intelligent people can often lose arguments)
One of the most infuriating experiences possible is arguing with someone who’s convinced they’re right when you know full well that they’re wrong, and can prove they’re wrong with facts and logic, but still they won’t budge. I once witnessed a heated fight between two people, one of whom was adamant that this is the twentieth century, not the twenty-first, because, “It’s twenty fifteen? Duh!” That was their actual argument.
Contrast this with the psychological phenomenon known as “impostor syndrome.” High achievers in many fields persistently underestimate their abilities and achievements despite having actual evidence of these things. There are many social elements to this. For instance, it’s particularly common in women who achieve success in a traditionally male-dominated environment (aka most of them) so they are likely to be influenced by stereotyping, prejudice, cultural norms and so on. But it’s not limited to women, and one of the more interesting aspects is that it predominately affects high achievers—those people with a typically high level of intelligence.
Guess which scientist said this shortly before his death: “The exaggerated esteem in which my lifework is held makes me very ill at ease. I feel compelled to think of myself as an involuntary swindler.”
Albert Einstein. Not exactly an underachiever.
These two traits, impostor syndrome in intelligent people and illogical self-confidence in less intelligent people, regularly overlap in unhelpful ways. Modern public debate is disastrously skewed due to this. Important issues such as vaccination or climate change are invariably dominated by the impassioned rantings of those who have uninformed personal opinions rather than the calmer explanations of the trained experts, and it’s all thanks to a few quirks of the brain’s workings.