University of Melbourne
Introduction: The Basic Tenets of Scientific Realism
Scientific realism consists of two key tenets. The first is that science aims at truth, including truth about unobservables and truth based on ampliative inference. The second is that we can justifiably believe that our successful scientific theories achieve, or at least approximate, that aim. The contemporary debate on scientific realism pivots around these issues. Part I of this dissertation will be concerned with the first tenet; Part II, with the second. Before elaborating on these tenets, to acquire a more robust picture of the position, we can identify some of the related foundational theses on which these key claims of scientific realism rest.
In opposition to, for instance, solipsists, the scientific realist insists that there exists an “external” world with which we interact. And, contra social constructivists, this world is one whose events, processes, and/or entities are not contingent on our beliefs. Scientific realists also take truth to be objective and to express a correspondence relation between statements and the world. Such a conception of truth is juxtaposed against those espoused by internal realists (eg., Hilary Putnam, Brian Ellis). Against idealists (eg., George Berkeley), the scientific realist maintains further that we can be justified in believing that the objects we observe exist and that our basic claims about their observable properties are true. In contrast to classical instrumentalists (eg., Ernst Mach), positivists (eg., Moritz Schlick, Rudolf Carnap), as well as fictionalists, operationalists, and phenomenalists, the scientific realist construes scientific theories literally. Most terms contained in scientific theories are intended to refer to real entities. Scientific realists hold further that, in general, theory change in science has been rational and progressive. This view stands in opposition to relativists (eg., on occasions, Paul Feyerabend, Thomas Kuhn) and most contemporary sociologists of science. Moreover, scientific realists tend to espouse the view that progress in science is determined by the extent to which its primary aim is achieved (or the degree to which that aim is approximated).
These tenets of scientific realism serve collectively to provide a framework within which the contemporary debate on scientific realism takes place. Most prominent contemporary opponents of scientific realism -- for instance, Bas van Fraassen and Larry Laudan -- either assume or set aside this framework. As noted above, the contemporary debate on scientific realism hinges primarily on two key tenets, one axiological, one epistemological. Expressing these theses more explicitly:
Axiological Scientific Realism: science aims, primarily, to express true statements about the world.
Epistemic Scientific Realism: we can be justified in believing that successful scientific theories are (approximately) true.
How are these tenets related? For the large majority of philosophers in the debate, axiological realism is assumed to rest on epistemic realism. I attribute this to the fact that nearly all, on both sides of the debate, take progress in science to be measured by the achievement of science’s primary aim (or at least the degree to which that aim is approximated). For those who embrace this restriction, we can see that construing science as successful, progressive, and rational requires that we be justified in believing that science has achieved (or at least approximated) its aim. That given, axiological realism requires epistemic realism. In accord with this point, the contemporary debate on scientific realism is by and large played out in the epistemic arena. Part I of this thesis will be a critique of epistemic realism. In Part II of this dissertation, I will argue -- against most in the debate -- that axiological realism does not require epistemic realism. This will involve, among other things, denying the realist’s conception of how progress in science is measured. More specifically, Part II will constitute a defense of an axiological realism that is independent of epistemic realism.
