Stephen asked:

Can a philosopher be regarded as a realist if they admit of subjective elements in perception?

How does a philosophy that accepts subjective elements in perception truly differ from Cosmothetic
Idealism or even Idealism, or is it capable of refuting them without admitting some form of "common
sense" or relying on consensus?

For example, in the old folk tale of the elephant, the three blind men each apprehend a "different"
object: a snake, wall, or pillar-like object. How can we distinguish that there are real objects in
themselves, without making an assumption and/or relying on "common sense" or social consensus,
when sometimes our actual senses differ — in other words, we get different "pictures" even if we all
do in fact apprehend the same object? Obviously this is an insignificant factor most of the time, but it
still can happen.

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1) Why not? The problem here is that you're thinking of "admit of" as implying existence. But think of
hallucinations. Think of simple errors of perception. Think of optical illusions. Do we have to say that
such things "exist", as real objects, just because we admit that we perceive them? No, of course not.
And the same argument holds for other subjective elements in perception. The question then
becomes where the subjective "stops", to put it crudely, and the objective "begins". There is no
certain or definite answer to that question, as is obvious if you consider the classes of examples I've
given you. But one can certainly be a realist and admit that one can have optical illusions.

2) Well I think that you can see the general answer to this from my first answer.

3) But the situation is even worse, because we must ask: what does consensus really add? If the
three blind men felt the same parts of the elephant, and they were all having kinesthetic
hallucinations, then they might all think it felt like a worm, or a brick wall, right? And how do they know
that they aren't, and that it doesn't? This is a very nasty and classical question, best answered, in my
opinion, by Kant. Briefly and sloppily, he states that we can notknow what "reality" is "really" like, that
what we do is find patterns in a kind of ambient chaos, and those patterns are derived in great part
from internal parameters and constructs. But there are other answers to this question, of which
Idealism is one. Many people today also argue for a kind of direct realism, where, barring
hallucinations (and how we identify those doesin these theories depend on consensus), we do
perceive reality as it is.

Some of these might help:

Johnson, M. (1993). Moral imagination: implications of cognitive science for ethics.Chicago, The
University of Chicago Press.

Kant, I. (1996). Critique of pure reason.Indianapolis, IN, Hackett Publishing Company, Inc.

Kitcher, P. (1992). "The naturalists return." The Philosophical Review101(1): 53-114.

Kitcher, P. (2002). "On the explanatory role of correspondence truth." Philosophy and
Phenomenological ResearchLXIV(2): 346-364.

Martin, M. G. F. (2002). "The transparency of experience." Mind and Language17(4): 376-425.

Millikan, R. G. (1991). Language, thought, and other biological categories: new foundations for
realism.Cambridge, MA, The MIT Press.

Quine, W. V. O. (1951). "Two dogmas of empiricism." The Philosophical Review60(1): 20-43.

Schlagel, R. H. (1986). Contextual realism.New York, Paragon House Publishers.

Walker, R. C. S. (1989). The coherence theory of truth: realism, anti-realism, idealism.New York, NY,
Routledge.

Steven Ravett Brown