Charles Spearman believed we have one of these that underlies specific mental abilities. He also helped develop factor analysis (a statistical procedure that identifies clusters of related items).
Primary Mental Abilities
Thurstone came up with that our intelligence may be broken down into seven factors (word fluency, verbal comprehension, spatial ability, perceptual speed, numerical ability, inductive reasoning, memory).
Alfred Binet published these in France.
Theory was led to by Thorndike’s article on animal intelligence.
William Stern developed the formula for this after studying the intelligence tests.
Robert Yerkes developed the Army Alpha and Beta Tests which were used with new recruits in the US Military.
Edward Thorndike proposed the know-how involved in comprehending social situations and managing oneself.
Wechsler-Bellevue Intelligence tests were published and became the most widely used.
Jean Piaget published his “Psychology of Intelligence.”
Howard Gardner introduced this theory which explains that intelligence is something to be used to improve lives, not to measure and quantify humans.
According to Earl Hunt, verbal intelligence scores are predictable from the speed with which people retrieve information from memory and in the words of Philip Vernon, “faster cognitive processing may allow more information to be acquired.”
Sternberg’s three intelligence (analytical, creative, practical intelligence)
John Duncan found that the frontal lobe (just about the outer edge of the eyebrows) may be a global workspace for organizing and coordinating information since various brain areas seemed to converge there.
"History of Psychology 387 BC to Present at AllPsych Online." Psychology Classroom at AllPsych Online. N.p., n.d. Web. 16 Jan. 2013. http://allpsych.com/timeline.html.
Myers, David G.. "Intelligence."Psychology. Ninth ed. New York, NY: Worth Publishers, 2010. 405-439. Print.