The Identity of the Indistinguishables
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The Identity of the Indistinguishables

Two entities that do not have any properties allowing to distinguish them should be seen as a single entity

This principle was probably first formulated by the philosopher and mathematician Gottfried Wilhelm Leibniz (a precursor of cybernetics and artificial intelligence, with his "calculus of thought") in the Monadology. It can be derived from the principle of Occam's razor, which implies that if there is no reason why two things should be distinguished then it is better to just identify them, so that one entity is left rather than two.

A similar idea underlies the Pauli Exclusion Principle in quantum physics, which states that no two particles ("fermions") can be in the same state at the same moment (otherwise, they would be indistinguishable and therefore there would be only a single particle). A more modern, cybernetic formulation, used by Gregory Bateson, is that of "a difference that makes a difference": distinctions are only useful insofar that they lead to further distinctions. If the initial distinction does not allow you to make any further distinctions, you should better drop it. This "relational" interpretation where the value of a distinctions depends on the further distinctions it is connected with can be formalized as the "bootstrapping axiom". It also underlies the microscopic interpretation of the principle of causality (identic causes have identic results), and a generalized version of empiricism, which says that postulated entities in a theory should (directly or indirectly) lead to observable differences.

Copyright© 1995 Principia Cybernetica - Referencing this page

F. Heylighen,

Sep 19, 1995


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