What is it?

The scientific idea of general intelligence, often called 'g', was initially introduced by Charles Spearman in 1904. According to Spearman, people have varying amount of general intelligence that are used in most cognitive tasks. Often overlooked, Spearman also proposed that there are specific intelligences that are used within particular areas that are not related to other cognitive tasks. For example, a specific intelligence may be a high verbal ability that helps a person articulate and share his or her thoughts.