popper-logic-scientific-discovery

some observations on quantum theory 245
The belief in causality is metaphysical.* 3 It is nothing but a typical
metaphysical hypostatization of a well justified methodological rule—
the scientist’s decision never to abandon his search for laws. The metaphysical
belief in causality seems thus more fertile in its various
manifestations than any indeterminist metaphysics of the kind advocated
by Heisenberg. Indeed we can see that Heisenberg’s comments
have had a crippling effect on research. Connections which are not far
to seek may easily be overlooked if it is continually repeated that the
search for any such connections is ‘meaningless’.
Heisenberg’s formulae—like similar statements which can only be
corroborated by their statistical consequences—do not necessarily lead
to indeterminist conclusions. But this in itself does not prove that there
can be no other empirical statement which justifies these or similar
conclusions: for example the conclusion that the methodological rule
mentioned—the decision never to abandon the search for laws—
cannot fulfill its purpose, perhaps because it is futile or meaningless or
‘impossible’ (cf. note 2 to section 12) to search for laws and for singular
predictions. But there could not be an empirical statement having
methodological consequences which could compel us to abandon the
search for laws. For a statement supposed to be free from metaphysical
elements can have indeterminist conclusions only if these are
falsifiable.* 4 But they can be shown to be false only if we succeed in
formulating laws, and in deducing predictions from them which are
corroborated. Accordingly, if we assume that these indeterminist conclusions
are empirical hypotheses, we ought to try hard to test them, i.e. to
falsify them. And this means that we ought to search for laws and predictions.
Thus we cannot obey an exhortation to abandon this search
without repudiating the empirical character of these hypotheses. This
shows that it would be self-contradictory to think that any empirical
hypothesis could exist which might compel us to abandon the search
for laws.
I do not intend to show here in detail how so many attempts to
* 3 Compare with the views expressed here, and in the rest of this section, chapter *iv of
the Postscript.
* 4 This, though valid as a reply to a positivist, is misleading as it stands; for a falsifiable
statement may have all kinds of logically weak consequences, including nonfalsifiable
ones. (Cf. the fourth paragraph of section 66.)