Charles Spearman (1920s) proposed the existence of “general intelligence,” which was named as “g” factor. Howard Gardner (1983) proposed the existence of seven categories of intelligence (multiple intelligences).
J.P. Guilford (1967) proposed the concepts of convergent and divergent intelligence. The convergent intelligence is measured by the traditional intelligence tests.
Hebb (1980) proposed that the structure of brain alters with experience and people have two types of intelligence, i.e. intelligence A and intelligence B. Intelligence A is the heritable or innate intellectual potential. Intelligence B is the observed intelligence, which develops or shapes under the influence of experiences and other factors.
Thus, the blanks can be filled with “g” factor; multiple intelligences; convergent and divergent; intelligence A; intelligence B.