Which theorist is credited with the 180-factor, three-dimension structure of intellect?

• A. Spearman
• B. Thurstone
• C. Guilford
• D. Vernon

Answer: (C)

Guilford’s Structure of Intellect is being tested here. He proposed that intelligence isn’t a single factor but runs along three dimensions: operations (the kinds of mental activities), contents (the type of material being processed), and products (the form in which the response is expressed). When you combine these dimensions—five operations, six contents, and six products—you get 5 × 6 × 6 = 180 distinct factors of intellect. This 180-factor, three-dimension model is Guilford’s distinctive framework, setting it apart from other theorists who emphasized a general intelligences or a smaller set of abilities. Spearman centers on a general factor (g); Thurstone proposed several primary mental abilities; Vernon outlined a hierarchical structure with general and group factors.