In the course of a study of elementary particles, an analysis is given of a fundamental presupposition of many research programs, namely the belief in the ultimate unity of physics. It is argued tht this unity-idea is incorrect. By classical physics, relativity theory and quantum theory three distinct structures of nature are revealed. Next, the essential aspect of measurement, that a measurement always results in a record, is analysed. Recording implies irreversibility and entropy production. In modern elementary particle physics the (...) record itself is all important, and therefore the entropy production due to measurement is essential. It is argued that this aspect of measurement will play a central role in a distinct theory concerning fundamental characteristics of elementary particles, revealing a fourth structure of physical reality. Some basic notions of this new theory are proposed. Finally the meaning of irreversibility on the micro-level of elementary particles is discussed, in connection with the concept of time. (shrink)

Whenever an adequate theory is found in science, we will still be left with two questions: why this theory rather than some other theory, and how should this theory be interpreted? I argue that these questions can be answered by a theory of system relations. The basic idea is that fundamental characteristics of systems, viz. those arising from the general systemic nature of those systems, cannot be comprehended with the aid of discipline-specific methods. The systems theory required should commence with (...) an analysis of the qualitatively different relations possible between systems, because it is precisely the nature of those relations that determines the basic structures of systems. That the theory of the fundamental system relations and their ontological and epistemological implications is indeed able to provide the answers sought is demonstrated in theoretical physics and Plessner's analysis of the basic structures of plant, animal and human being. (shrink)