REALISM AND ANTI-REALISM

In an attempt to free the idea of the laws of nature from something that has legislative or regulative power – a hangover, perhaps, from pre-scientific intuitions of God-ordained fate – we have spoken of “the habits” of nature, with reference to the uniformity of its manner of unfolding. The habits are not distinct from nature and hence are not imposed on it. Things don't “obey” their own habits. If those habits are universal and unalterable, however, they are no more open to negotiation than would be the most rigid and “pushy” laws.

But an important point remains: if we close the distance between nature and its patterns of behaviour by replacing “laws” with “habits” we correspondingly widen the distance between nature and the laws of science. At the very least, the laws of science are laws about nature and so cannot be identical with the latter. The question therefore arises as to whether, or to what extent, the laws of science are, or could ever be, undistorted articulations of the habits of nature. Are they faithful portraits of how nature fundamentally “goes” and of the stuff in which those habits are expressed; or are they merely useful instruments – cognitive tools to assist us to predict and manipulate the natural world? There are reasons for favouring the latter – the so-called instrumentalist or anti-realist interpretation of the laws of science.

The most obvious come from reflection on the history of science which suggests that all laws hitherto discovered have proved to be provisional, approximate, incomplete, or sometimes plain wrong. They are up for endless revision or replacement. To this process, there seems to be no end in sight. The incompatibility between the two most powerful and fundamental scientific theories – quantum mechanics and general relativity – is a striking challenge to faith in a gradual progression towards an entirely realistic portrait of the habits of nature. The increasingly desperate but unsuccessful attempts to unite and reconcile those two grand theories – of which 10-dimensional string theory is only the most absurd and inconceivable – gives ammunition to the instrumentalist position.