In a recent New York Review of Books article entitled “What Your Computer Can’t Know” philosopher John Searle provides a fairly helpful analysis of the different kinds of knowledge. He states:

The distinction between objectivity and subjectivity looms very large in our intellectual culture but there is a systematic ambiguity in these notions that has existed for centuries and has done enormous harm. There is an ambiguous distinction between an epistemic sense (”epistemic” means having to do with knowledge) and an ontological sense (“ontological” means having to do with existence). In the epistemic sense, the distinction is between types of claims (beliefs, assertions, assumptions, etc.). If I say that Rembrandt lived in Amsterdam, that statement is epistemically objective. You can ascertain its truth as a matter of objective fact. If I say that Rembrandt was the greatest Dutch painter that ever lived, that is evidently a matter of subjective opinion; it is epistemically subjective.

Underlying this epistemological distinction between types of claims is an ontological distinction between modes of existence. Some entities have an existence that does not depend on being experienced (mountains, molecules and tectonic plates are good examples.) Some entities exist only so far as they are experienced (pains, tickles and itches are examples.) This distinction is between the ontologically objective and the ontologically subjective. No matter how many machines may register an itch, it is not really an itch until somebody consciously feels it: it is ontologically subjective.

This seems quite useful and is worth keeping in mind. But I feel there are blurry lines that need to be acknowledged. Let’s look at what a mountain is. We can break that entity into a couple of “parts” – there’s the fact that the mountain is there in some objective sense (some people who question the very nature of reality might dispute this point) and then there is my observation of the mountain, my act of seeing* the mountain. The first part is objective, the second subjective. But let’s now look at an itch. An itch is similar to pain and caused by some minor degradation of your physical body. Maybe a bug bit you, maybe a wound is healing. The actual sensation of the itch is your sensory awareness of this degradation. So again, there are two components—the objective part (the biting bug or whatever it is) and the subjective (the itchy feeling.) My point being that a mountain and an itch are not all that different; they share these two components. An itch is really just a way of sensing the thing that attacked your skin.

* Sight is really the only sense that allows one to get a clear representation of a mountain. There are other objects, however, that one can use various senses to appreciate. A lasagna can be seen, smelled and tasted for example.

And going to the first quoted paragraph: We can say that it is objective to say that Rembrandt lived in Amsterdam, but is it really? It is dependent on us agreeing to the human convention that this particular place on earth is called Amsterdam and that this particular bundle of historical matter was called Rembrandt. For the statement to be true we (the observer of the statement) need to agree to various taxonomies. If I could get everyone to agree on some system by which we could judge art, I might very well be able to objectively claim that Rembrandt was the greatest Dutch painter. That really is the difference between the two statements: how may people agree on the terms. (There is near universal agreement on terms like “Rembrandt” and “Amsterdam, less so on “great painter.”)

It may seem I’m trying to be difficult here, but I’m merely pointing out how hard it is to really define these terms.