Spearman's structural theory of ability

The structure of ability is a very important research topic in modern psychology. Analyzing the factors of the structure of ability is of great significance to the in-depth understanding of the nature of ability, the rational design and measurement of ability, and the scientific formulation of the principles of ability training. In addition to Spearman's two-factor theory of ability structure, there are several other theories as follows: American psychologist Vernon proposed the theory of intellectual hierarchy. Vernon took Spielman's general ability factor as the highest level, under which two major groups of factors are included, namely, the verbal and educational aspect of the ability factor, and the operational and mechanical aspect of the ability factor; the third level is the group of minor factors; and the fourth level is the special factors. It is thus clear that Vernon's theory of the hierarchy of intelligence is merely a deepening of Spearman's two-factor theory.