The Weber–Fechner law is a confusing term, because it combines two different laws. Some authors use the term to mean Weber's law, and others Fechner's law. Fechner himself added confusion to the literature by calling his own law Weber's law. Ernst Heinrich Weber

Ernst Heinrich Weber

Ernst Heinrich Weber was a German physician who is considered one of the founders of experimental psychology.Weber studied medicine at Wittenberg University...

 (1795–1878) was one of the first people to approach the study of the human response to a physical stimulus

Stimulus (physiology)

In physiology, a stimulus is a detectable change in the internal or external environment. The ability of an organism or organ to respond to external stimuli is called sensitivity....

 in a quantitative

Quantitative research

In the social sciences, quantitative research refers to the systematic empirical investigation of social phenomena via statistical, mathematical or computational techniques. The objective of quantitative research is to develop and employ mathematical models, theories and/or hypotheses pertaining to...

 fashion. His law states that the just-noticeable difference between two stimuli is proportional to the magnitude of the stimuli.