In our Lilienfeld text, a topic that was covered was the development of g or general intelligence. This concept was first introduced by Charles Spearman, who believer that the positive correlations among intelligence test items must be related by a single factor. The basic concept that tho book gives of g, is that is has to do with an individuals "mental energy". This brings up a lot of controversy among intelligence researches, because it implies that some people are smarter than others. I agree with this completely, I think everyone has varying levels of intelligence, because if everyone had the same level of intelligence and understanding, then every concept ever thought up by humankind would be universally understood. This is, however, not the case at all. Imagine if everyone had the same amount of ability as everyone else. The world would be a very boring, melancholy place to live, because everyone could do everything that anyone could. I think that Spearman was very on track with his concept of g. He also goes on to discuss the s factor. This is our specific ability to excel in a certain area. For example, some people are very good at math and manipulation of equations, but could be bad at understanding various psychological or philosophical concepts. This entire model that Spearman came up with is a very sound one, in my opinion. It explains how everyone is good at something and lets us celebrate the diversity of abilities that make up humankind.
source: Lilienfeld text