Genidentity

The term genidentity 1922 was influenced by Kurt Lewin in his habilitation thesis " The notion of genesis in physics, biology and evolutionary history " and today is probably the last indication of Lewin's influence on the philosophical theory of science. The original concept was, however, little analysis, but rather extracted from philosophers such as Rudolf Carnap, Hans Hermes and Hans Reichenbach from its context and integrated into their own theories, such as Reichenbach's theory to the topology of space-time or Hermes ' axiomatization of mechanics.

Lewin's original idea was to compare the term genidentity within the various sciences to reveal with his help, the characteristic structure of these sciences and thus to classify new.

Classification of the natural sciences

In his habilitation thesis compares Lewin physics ( to which he also includes the chemistry) and biology (which he divides into organic biology and evolution ). A comparison of this kind presupposes that it is possible to find equivalent terms in both sciences. According to Lewin, the concept of genidentity meet this requirement.

Lewin defined as genidentity Existentialbeziehung, which is the genesis of a body from one moment to the next is based. This interpretation is in accordance with what we think is usually for a single object, in reality from a variety of entities, as if the phases of an object at different times. Two things are therefore not identical because they have the same properties in common, but because one has emerged from the other.

Here Lewin distinguishes between partial and total genidentity ( in the original wording: "partial" or " completely "). This is due to the conceptual difficulty posing shared objects. For example, an object can be divided into several parts in the course of its development. If we follow such an object in time, certain circumstances may only a small part of it remain. Lewin formulated that two objects that exist at different times, are partially genidentisch, when at least a portion of the latter object was already contained in the former. In contrast, two objects are exactly then totally genidentisch if there is no any point of a different two objects object that is with one of the affected objects partially genidentisch.

In addition, Lewin developed the idea to consider physical body as members of a development chain. According to this approach, there are between two totally syngeneic bodies at any intermediate point, an object that is totally genidentisch with both. Thus genidentity implies the existence of an infinite number of intermediate points. Herein Lewin sees an analogy between physical bodies and real numbers, or the so-called Dedekind cuts ( after Richard Dedekind named construction method to represent the real numbers as Dedekind cuts of rational numbers ).

Genidentity has defined several properties such as symmetry, transitivity, density and continuity. Will this be considered in the light of modern logical standards, it quickly becomes clear that Lewin had the right intuition, though it were not the advantages of a highly developed terminology of definition theory and symbolic logic.

The term genidentity as such was not explicitly discussed in the experimental sciences, but rather formed a tacitly presupposed background assumption. Lewin, it is thanks to that this term was examined for the first time in more detail what now came in view of its much more famous achievements in Gestalt psychology into oblivion.

Credentials

The concept of genidentity - A study of the science theoretical writings of Kurt Lewin. Master's thesis by Martin Becker, submitted at the Johann Wolfgang Goethe University Frankfurt am Main, Department of Philosophy and Historical Sciences, 1998.

• Philosophy of Science