Charles Spearman was an English military-man turned Psychologist. He studied Wundt and Kulpe in Germany, and was a well-known distinguished German psychologist. After taking an academic break to fight in the Boer war (1899-1902), Spearman started reading Galton’s articles and books, which impressed him.
Spearman performed various experiments on village schoolchildren. Based on the experimental patterns of Galton and his tests the results were further strengthened and his belief was that there was a relation between the intelligence of a person and his sensory capabilities.
Spearman found out that sensory acuity of a person has a positive correlation with “cleverness in school”. He published these results in year 1904 in an article known as “General Intelligence, Objectively Determined and Measured”. Thereafter, he got the position of director of Psychology Laboratory at the University of London.
Spearman believed that there were several factors responsible for the intelligence of a person. He laid out the study procedures of ‘factor analyses’, which were complex statistical data based on the correlations of the test results.
Spearman found out that the intelligence could be described by two factors namely specific factors and general factors. Individual differences in a variety of subjects could be referred to as ‘specific factors’ and the general kind of intelligence, which is shared by many, is referred as ‘general factors’. This is also known as ‘Two factor theory of intelligence’
Spearman’s views of Intelligence are summarized as follows based on ‘Factor analyses’ and ‘Two factor theory of intelligence’:
1. Intelligence according to Spearman is inherited and is of unitary nature.
2. Intelligence quotient or IQ is the measurement of general intelligence.
3. Success of measuring intelligence is based on sophisticated statistical techniques.