Editing Francis Galton (section)

===Differential psychology===
{{main|Differential psychology}}
Galton's study of human abilities ultimately led to the foundation of [[differential psychology]] and the formulation of the first mental tests. He was interested in measuring humans in every way possible. This included measuring their ability to make sensory discrimination which he assumed was linked to intellectual prowess. Galton suggested that individual differences in general ability are reflected in performance on relatively simple sensory capacities and in speed of reaction to a stimulus, variables that could be objectively measured by tests of sensory discrimination and reaction
time.{{sfn|Jensen|2002|pp=145–172}} He also measured how quickly people reacted which he later linked to internal wiring which ultimately limited intelligence ability. Throughout his research Galton assumed that people who reacted faster were more intelligent than others.