What is Scientific Realism?

The upshot of my opening was meant to be this: whatever scientific realism is, if it is a philosophical position, it does not include such claims as that electrons, or other entities postulated in scientific theories, are real.

And similarly, whatever may be an empiricist position, contrary to scientific realism, if it is a philosophical position, it cannot include the claim that such entities do not exist. On questions of existence, as on all questions of brute fact, both sorts of philosophical positions must be mute.

My own view, constructive empiricism, may well have other eye-brow raising shortcomings, but it does not include any claim, whether positive or negative, about whether the sciences are successful in their endeavors. I take it as common knowledge that the sciences are indeed successful by many important criteria, both practical and intellectual, and that science provides us with a paradigm example of rational inquiry. I also take it as commonly known among scientists that they are as yet unsuccessful in some respects. Scientists address questions about what there is in the natural world and what it is like, but these are matters aside from the basic question at issue in philosophy: What Is Science?

Remarkably, though, there are on the contrary scientific realists who present their position as centering on claims about what there is in the natural world and what it is like. These claims associate the philosophical position with concurrently accepted scientific theories, which the scientific avant-garde may well be ques­tioning but the philosopher asserts to be true.^[20]

Rather than quibbling with realists in general or paint them all with the same brush, let us focus on careful, thoughtful scientific realist philosophers who present this aspect of the position very guardedly, in a form so general that it is subject to less audacious interpretation.

to involve the conjunction of two theses: (1) an independence thesis: our judgments answer for their truth to a world which exists independently of our awareness of it; (2) a knowledge thesis: by and large, we can know which of these theses are true. (Papineau 1996, 2).

Taking this very strictly, this would mean that a scientific realist today would say, about the statement that electrons exist, (1) that it answers for its truth to a world existing independently of our awareness of it, and (2) that we can know whether or not it is true.

Together these do not imply that electrons exist, only that we can know, that it is possible to know, whether or not they do. So this position of scientific realism could be held by someone who also holds either (a) that electrons do not exist or (b) that we (can but) do not know whether or not they exist.

It is useful here to recall Peter Forrest's terms, scientific gnostic (someone who believes that our currently accepted scientific theories are true) and scientific agnostic (someone who suspends belief as well as disbelief with respect to currently accepted scientific theories). So here is a point of logic, which will not escape the careful reader: on Papineau's understanding at least, the scientific gnostic/agnostic distinction cuts across the scientific realist/anti-realist distinction. There can be philosophers of all four sorts: scientific realists who are scientific gnostics as well as ones who are scientific agnostics, and of course philosophers who are not scientific realists but are scientific gnostics as well as ones who are scientific agnostics.

Allow me to make a proposal, in two parts.

First of all, let us consider only philosophical positions that agree on Papineau's condition 1, his independence thesis. However broadly or narrowly this is construed, I take it that it is in accord with Michael Dummett’s proposed usage for “realist”: to take a realist position on some topic is to hold that a certain associated discourse has ‘objective’ truth conditions.

Even adding Papineau’s condition 2 we do not arrive at a substantive view of what science is. Papineau’s conditions merely narrow the classification of science to an inquiry into objective fact, whose results can be known to be true-which applies equally to, for example, investigative journalism about politics.

So, what is to be included to formulate scientific realism, beyond this semantic realism? And what is to be included in an empiricist position, a rejection of sci­entific realism, beyond this semantic realism?

As second part, then, I would like to propose again, that it should be, in each case, a distinctive answer to the question What Is Science?, and that this should be an answer which purports to identify the aim of scientific inquiry, in the sense in which stating the aim amounts to specifying its most basic criterion of success.

Needless to say, that question needs spelling out before we will have enough clarity to see what will count as a relevant answer. I will return to this below, and to end I will lay out some recently discussed positive proposals for the investigation of what criteria are actually in force in scientific theory and practice. But I would like to first clear some more of the muddied waters that presently surround these sci­entific realism debates.

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