International Encyclopedia of Systems and Cybernetics

The classical concept of scientific method left mental, psychological and consensual aspects out of the picture, thus creating the illusion of objectivity.

The constructivist view explains various formerly puzzling aspects:

- How could we get scientific controversies (some of them quite heated) and "revolutions" (T. KUHN).

- Why and how should scientific theories be falsified (K. POPPER).

- Why did we need a theory of logical types (B. RUSSELL – A.N. WHITEHEAD) and why could no scientific – or, for that, logical – explanation be self-validating (K. GÖDEL).

H. MATURANA puts the constructivist viewpoint in this way: "As scientists we make scientific pronouncements. These pronouncements become validated through experiments that we make, according to scientific method. This method can be retraced in the following way:

a) Observation of a phenomenon, seen as a problem to be solved;

b) development of a hypothesis in the guise of a deterministic system able to produce a phenomenon isomorphic to the observed phenomenon;

c) generation of a situation or process which, in coincidence with the proposed hypothese, could be observed as the predicted phenomenon;

d) observation of the predicted phenomenon" (1982, quoted by P. HEJL, 1985, p.111) (this compiler's italics).

Every italicized term bears a mental or psychological load and, consequently, the results cannot be taken for an absolute representation of reality.

Moreover, the construction of so-called scientific truth is altogether a matter of consensus among scientists, after due debate. And still, such consensus is always provisional, until someone challenges it with new observations or hypotheses. In this case, the whole process must be rehearsed, with unforeseeable results.