Spearman vs Thurstone

Welcome back! I promise, we are almost done with intelligence! There is just a lot to talk about and a lot of differing opinions that need to be covered before we move on. In this blog, we're going to be talking about Charles Spearman and Louis Thurstone. They have two different opinions on how we think and how smart we really are!

First off, Charles Spearman. Spearman was an English psychologist whose focus was on intelligence and statistics. Spearman is well known for his idea of general intelligence, or g factor. In the early 20th century, Spearman tested children from different schools on unrelated school subjects to see how they performed. Spearman saw that children that did well on part of the test also did well on a different part(s) of the test. He labeled this as g, an underlying intelligence that can affect IQ tests. These children that did well on multiple parts of this test, he said, had a high g, or a high general intelligence. Overall, they may just be smarter than others.

A basic summary of Spearman's theory is that we all have a basic intelligence (some stronger than others). This basic intelligence (this "g") will predict our ability to perform successful in all academic areas. I do like Spearman's idea because it goes along with Gardner's idea of 8 intelligences. You can have more than one strong area of intelligence. Areas tend to correlate, much like I mentioned in the 8 intelligences blog. For example, I said a couple of blogs ago that if you have a strong spatial intellect, you may have a strong bodily-kinesthetic intellect.
There are some flaws with Spearman's theory, though. Humans are amazing beings. We cannot be defined by one number, one g score. We are too diverse, our minds are too wide-spread and different to all be defined by a single number.

So we go on to Louis Thurstone, then. Louis Thurstone disagreed with Spearman's idea of one g score, one number that defined how intelligent we are. Thurstone didn't think that one number was informative enough for a person's intelligence, so he able to come up with seven factors that he said played into our intelligence. They are simply what Spearman added up to get one number, but Thurstone kept them broken down into seven so it was easier to see where a person excelled at. The factors are: word fluency, verbal comprehension, spatial ability, perceptual speed, numerical ability, inductive reasoning, and memory. Thurstone's attempt at this was to show that we don't have a single g score, but several areas of intelligence. Unfortunately (at least for Thurstone), even after coming up with his seven factors, people who excelled at one area did well in another area, suggesting that there actually may be an underlying g score that can define how smart we really are.

All four of the men we have talked about (Sternberg, Gardner, Spearman, Thurstone) have very good ideas, but are differing in their ideas. It is very hard to put a definition to how we think and how our intelligences work. I actually agree with parts of all of their theories, but I couldn't pick just one that I agree with more than others.

This blog was a bit shorter than others, but it's a little easier to understand. Next time, we'll be talking about our last two intelligence guys: Alfred Binet and Lewis Terman! Thanks for reading!