Psychology

Psychology? It's all in the mind.

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Weber's law

or Weber-Fechner law

In psychophysics, a historically important law quantifying the perception of change in a given stimulus. Originated by the German physiologist Ernst Heinrich Weber (1795–1878) in 1834 and elaborated by his student Gustav Theodor Fechner, the law states that the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus. It was later shown not to hold for extremes of stimulation.

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