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Heisenberg, complementarity, quantum mechanics, scientific method, theory of measurement, psycho-physical parallelism


Continental Philosophy | History of Philosophy | Philosophy of Science


In this chapter "Conplementarity and the Scientific Method" of his Quantum Mechanics and Objectivity, Heelan argues that the philosophy of complementarity, although successful in providing physicists with a common language with which to describe quantum phenomena, also contains a theory about scientific method and about human knowing which is open to criticism. Heelan here criticises the following points arising out of the philosophy of complementarity: psycho-physical parallelism; the view that quantum mechanical properties are to be defined classically; and the perturbation theory of measurement. In the course of the criticism, he elaborates the distinction between two types of concepts with different logical structures; viz., operational or observational concepts which state a similarity between things judged on the basis of appearance or utility to us, and explanatory concepts which state a similarity between things judged on the basis of a self-defining set of different relations between things. Heelan thus shows how a physical concept is definable by any appropriate measuring-process. The description of the measuring­ process and, hence, the definition of the physical property involve the two classes of concepts described above, but in different ways. Thus one may regard the Indeterminacy Relations, not as stating limi­tations of our knowledge, but as describing more exactly the behaviour of individual systems.

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Originally published as "COMPLEMENTARITY AND THE SCIENTIFIC METHOD: A CRITICISM, Chapter Four in: Patrick A. Heelan, Quantum Mechanics and Objectivity (The Hague: Nijhoff, 1965), pp. 57-80.