Intelligence - Ability to learn from experience, solve problems, and use knowledge to adapt to new situations.
- Rational thought and reasoning
- The ability to act purposefully in an environment
- The ability to deal with the situations, in an effective manner, within an environment  
- Sternberg: Intelligence is the cognitive ability of an individual to learn from experience, to reason well, to remember important information, and to cope up with the demands of daily living.
Theories of Intelligence
a. G or G-Factor - is a statistic used in psychometrics to model the mental ability underlying results of various tests of cognitive ability. Developed in 1904 by psychologist Charles Spearman to account for imperfect correlations in IQ tests, this model is considered the first theory of intelligence.
- He found a trend for all such tests to correlate positively with each other called Positive Manifold.
- Spearman found that a single common factor explained the positive correlations among test.
- He interpreted it as the core of human intelligence that, to a larger or smaller degree, influences success in all cognitive tasks and thereby creates the positive manifold.
b. Fluid and crystallized Intelligence - (abbreviated Gf and Gc, respectively) are factors of general intelligence originally identified by Raymond Cattell.
- Fluid intelligence or fluid reasoning is the capacity to think logically and solve problems in novel situations, independent of acquired knowledge. It is the ability to analyze novel problems, identify patterns and relationships that underpin these problems and the extrapolation of these using logic. It is necessary for all logical problem solving, especially scientific, mathematical and technical problem solving. Fluid reasoning includes inductive reasoning and deductive reasoning.
- Crystallized intelligence is the ability to use skills, knowledge, and experience. It should not be equated with memory or knowledge, but it does rely on...