Charles Spearman and L. L. Thurstone were pioneers in the field of intelligence. They not only developed methods to assess and understand intelligence, but also developed theories about its structure and function. Methodologically, their approaches were not that distinct, but their theories of intelligence were philosophically very different --…

The practice of individual assessment has been moving toward the empirically derived Cattell-Horn-Carroll (CHC) theory of intellectual ability, which offers a hierarchical taxonomy of cognitive abilities. Current assessment tools provide varying adherence to operationalizing CHC theory, making clinical inference difficult. Expert consensus…

Word concepts have long been recognized as an integral part of intelligence, and word definition tasks are frequently used to measure them. Entire subtests requiring definitions, usually called vocabulary tests, are common; because of their apparent stability and comparability with overall intelligence, these subtests have been given a preeminent…