Graziano & Raulin
Research Methods (9th edition)
Gustav Theodore Fechner (1801-1887) was a German mathematician and physicist. Fechner conceived of a mathematical relationship between the non-material mind and material stimuli. He hypothesized an answer to the ancient mind-body problem--that the mind-body connection can be understood as a mathematical relationship between purely physical (material) stimuli and mental sensations. The sensations depend on the physical characteristics of the stimulation. That is, mental quality depends upon physical quality and the sensations have a predictable mathematical relationship to the physical quality.
Fechner developed laboratory methods of psychophysics, in which systematically controlled changes in intensity of stimuli could be mathematically related to reports of mental changes. The relationship, according to Fechner, is logarithmic, in that as one variable increases arithmetically, the other increases geometrically. He published the important work, Elements of Psychophysics, in 1860.
Fechner’s influence was critical in establishing that mental phenomena can be studied objectively, that these phenomena can be related mathematically to the stimuli used, and that psychology can be scientific.
Although it is Wundt who is credited with founding experimental psychology, Fechner and Weber carried out the research and created the procedures and concepts that Wundt later used in his own work some 15 years later. Indeed, Wundt even recognized Fechner’s primacy.