Realism vs. Antirealism
THE METAPHYSICAL SIDE OF THE STORY:
Metaphysical Realism: the idea that reality exists independently of our thoughts and perceptions about it. Such a
world can be thought of as an objective reality because it is not a product of our thoughts and actions.
Metaphysical Antirealism: the idea that no reality exists independently of us. The world is nothing more than our
subjective experiences; it’s a composite of our thoughts, perceptions and actions.
THE EPISTEMIC SIDE OF THE STORY
Epistemological Realism: Can know anything about the world that exists independently of our minds, or are we
merely stuck in the position of knowing the world only as it appears to us? The epistemological realist thinks the
answer is yes.
It would seem that the epistemological realist needs to be able to demonstrate that our knowledge actually gets at
the way things objectively are, though not all thinkers have agreed with this, assuming instead that it should just be
an unquestioned default assumption.
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Notice that all epistemological realists presuppose that there exists a mind-independent reality. You can’t
be an epistemic realist without being a metaphysical realist too. But the opposite need not be the case.
Epistemological Antirealism: does not think we are capable of demonstrating that our knowledge about the
world is actually about a world that exists independently from our thoughts about it. It may be out there for all we
know, but there is no way to definitely prove that. This is a much weaker claim than the claim made by the
metaphysical antirealist.
The realism/antirealism divide can also be cast in terms of the more narrow issue of what we think our
scientific theories tell us about “the world.”
Scientific Realism: (“we discover things about nature”): refers to a specific kind of realism, namely, realism about
the content of our scientific theories (and models). It supposes that the processes, entities, relations, etc. (whether
those things be observable to us or unobservable) appealed to in our theories refer to real (mind-independent)
processes, entities, relations, etc. Science describes to world as it is “in and of itself.”
[Note: we can be realists or antirealists about theories themselves or theoretical objects or both.]
Scientific Realism is often defined on one of two ways:
1. It can be defined in terms of the success in science. Successful theories are accorded a special status, that of
“being true” or at least “being closer to the truth.”
2. It can be defined in terms of what the aims of science are. Science aims at explaining/describing the world as it is
in and of itself, regardless of how successfully it does so. We can be pessimistic about our ability to achieve the
truth, but we can be too pessimistic. (If we are too pessimistic, we slide into the anti-realist camp.)
Commitments
No matter what brand of scientific realist you happen to be, you are generally committed to the following broad
claims.
1. There is a mind-independent world which science investigates; a “way that the world really is” and this
defines the truth science aims to achieve.
2. The theoretical terms (about entities, and processes, and laws, etc.) and models employed by our successful
theories are not just instruments of prediction; they are true of the world.
3. Our successful theories give us knowledge of the world.
How can we be confident that our theories get at the truth of things? We can have confidence in more mature
theories, those that have withstood rigorous testing, and ones that make successful novel predictions (which
means they are less likely to be ad hoc theories).
Arguments in Favor of Realism:
1. The “Miracle” Argument
2. The Corroboration Argument for unobservable entities
3. Explanation Argument: we can be realists about those parts of a successful theory (say, the theoretical
entities mentioned by it) if those parts are critical for explaining why those theories are successful.
4. We are justified in adopting a realist view about unobservable theoretical entities if we can experimentally
manipulate those supposed entities in such a way that it brings about specific results.
Antirealist objections to Realism:
1. Empiricist Objections:
a) If we assume knowledge is based on sense-experience, then we cannot have knowledge of
“unobservables.”
b) Theories are underdetermined by the observational data—so different conflicting theories can be
consistent with the data—thus the choice of which theory to believe (which one should count as true of the
world?) is also underdetermined. I.e., there is more than one theory that is empirically adequate to the
data; consequently, we do not have a good reason for prioritizing one theory over the other as the “true (or
truer) account of things.”
2. Social Construction Objection: what counts as evidence, theory, objects of science, knowledge, truth, or
even what counts as science is socially constructed in one way or another; therefore, we cannot assume
that what science talks about or theories it produces represent the way the world really is itself.
Scientific Antirealism (“we invent things about nature”): general position denying that the theoretical talk of
science should be taken to refer to things that exist independently of our theories, language, or point-of-view, etc.
Such antirealists tend to regard theories as having a purely instrumental value, insofar as they permit us to make
good predictions. [You can be a metaphysical realist and still be a scientific antirealist since you are just making a
very limited claim about at least some of our scientific theories as opposed to making a broader claim about our
knowledge of the world as a whole.]