Fluid intelligence (Gf) was hypothesized as the ability to solve novel problems by using reasoning, and crystallized intelligence (Gc) was hypothesized as a knowledge-based ability that was very dependent on education and experience.
Flydende intelligens (Gf) blev antaget som evnen til at løse nye problemer ved at bruge ræsonnement, og krystalliseret intelligens (Gc) blev antaget som en videnbaseret evne, der var meget afhængig af uddannelse og erfaring.