Source vonkries.de
Johannes von Kries was a German physiological psychologist, or what might now be called a neuroscientist, and student of Helmholtz. In color science, he is known as the father of chromatic adaptation models for his work on the coefficient theory of adaptation. He also made significant contributions to a variety of other fields including probability theory and the structure of the retina and human visual system.
von Kries published profusely (in German, with few works translated to English) on topics such as blood flow in arteries, duplicity theory, chromatic adaptation, zone theory, probability theory, physiology, psychology, and history. For example, observations of the Purkinje shift led von Kries to postulate the existence of two separate visual systems, rods, and cones, also referred to as duplicity theory. It is well known that Helmholtz described the trichromatic theory of color vision and participated in a famous academic dispute with Hering, the main proponent of opponent-colors theory. It is less widely recognized that von Kries was among the first proponents of the so-called zone theory of color vision that allowed for trichromatic receptors (the cones) and opponent processing of the visual information. It is not surprising that von Kries is sometimes referred to as the “greatest German disciple” of Helmholtz. Considering that Helmholtz’s students included the likes of Max Planck, Wilhelm Wien, Arthur König, A. A. Michelson, and Wilhelm Wundt, that is quite a statement.
In the second half of the nineteenth century, von Kries was applying probability theory to the evaluation of the effectiveness of new drugs. He realized that the computation of probability distributions depends on the classification of symptoms and pathologies into diseases, often very subjective data. Given that the important uncertainty was determined by the experimenters’ definition of events, he developed the logical foundations of a probability theory where the subjectivity of mental representations impacts the assignment of numerical values to probabilities. Interestingly, with some distortion and misunderstanding, these ideas passed on to J. L. Keynes and formed the core of his economic theory. In his book on the topic, von Kries developed a highly original interpretation of probability, illustrating it to be both logical and objective [1].
49.1 Chromatic Adaptation
This can be conceived in the sense that the individual components present in the organ of vision are completely independent of one another and each is fatigued or adapted exclusively according to its own function.
But if the real physiological equipment is considered, on which the processes are based, it is permissible to doubt whether things are so simple.
Indeed, things are not so simple, but yet von Kries’ theory forms the basis of all effective modern models of chromatic adaptation, including that embedded in the CIECAM02 system.