As I hinted at a while ago in my “How to develop intellectual success” post, I think that IQ is a pretty horrid way to describe intelligence in general. Plenty of people have already discussed the invalidity of the current IQ test and scale before (here’s probably the best one), so what I instead wanted to do was describe why I think that an IQ test/scale could never work in the first place.
I’ll start with the obvious but true argument that there are many different types of intelligence. The original idea behind general intelligence was that it was supposed to be a good measure of how fast you could learn things in general. There’s, of course, a big problem with that; we don’t learn everything by a given set of speed. Say, if we had really high acuity for maths and social skills, then we learn maths and social skills faster. But, if by chance we also have a low acuity for creative tasks like reading and writing, then we would learn these lower. The combination of all these elements is sort of a hodge-podge that could quite possibly go one way or the other on the scale but is typically going to land straight in the average. And, unlike examining the skills separately, this average really doesn’t teach us much.
In addition to this, I don’t think that there is a good way to measure these as opposed to, say, just general skills. Of course, if you are bad at reading and writing, or maths, or social skills, you can just go out to improve them. And, sure, you might not be able to improve it as much as someone with a natural disposition for the skill, you can still definitely get it to a point where it’s greater than you started. This conflicts with IQ’s main theory that the IQ that you’re born with stays the same. You can certainly improve your speed of learning by finding the right combination of methods for you, and you can certainly improve any of the different intelligences by just well-developed practice. Hell, I didn’t even catch some of the patterns in a standard IQ test the first time I took it; after I had found them, my score increased significantly.
IQ, however, is still good for some things. Perhaps the greatest example of this is the ability to diagnose mental defects like Down Syndrome and the like. That being said, there are likely better ways to turn this into a test specifically for detecting syndromes and other such things rather than just taking an IQ test.