As is often the case when I see an either-or question like the one in the title of this post, my knee-jerk reaction is to say, “I don’t know, maybe both?”. (I tend to be very suspicious of dichotomies, suspecting that many more are actually false than is commonly assumed.) In this case, after further reflection, I would definitely say both.
The folks over at The Christian Humanist have put together a really nice podcast all about epistemology. I highly recommend you head over to their site (also linked in the blogroll on the left), subscribe to their podcast feed, and give it a listen. In one part of their podcast, they discuss the relationship of epistemology to modern science, specifically by arguing that modern science actually contains elements of both a “rationalistic” epistemology, and an “empiricist” epistemology, even though it is commonly assumed to be largely described by the latter.
I have to agree, but first I need to explain what is meant by the terms “rationalism” and “empiricism” in this context. Now, I’m certainly no expert here, but from what I’ve been lead to understand, rationalism is a theory of knowledge that tends to emphasize the faculties of pure reason, although the Wikipedia article linked to above appears to define this as “idealism”. Perhaps someone who knows more about these distinctions can chime in here. Rationalism, thus defined, would be concerned in a scientific context with the building of models and theories, logical and mathematical, for which to make sense of the data of science and to make predictions about what new observations and experiments might show. On the flip side of this is empiricism, which is a theory of knowledge that emphasizes observational data, gathered by our senses, and by extension, our scientific instruments and observations and experiments utilizing those instruments.
The question in my mind is, which one of these epistemologies, if either, is primary in modern science? I myself have tended to lean toward an empirical view of things as having the final say in matters of science, and I think many (dare I say, most?) scientists would agree with me. What I mean is, that at the end of the day, all of our rationalizing–that is, our theories and models–can be overturned by new observations and experiments. On the other hand, I also think that theories in science are absolutely indispensable for at least a few reasons: 1) They help us make sense out of patterns we see in nature, which is what gives form to science and keeps it from being a mere collection of facts, 2) they make predictions about what new phenomena we might uncover once we have the technological capability of doing so, and theories are thus at least in part measured by how successful their predictions are, and 3), they guide the development of new ways of observing and experimenting to begin with. In this way, theory feeds back on experiment, which in turn tells us how well our theories are doing. So, with this way of looking at things, one can argue that both theories of knowledge are needed in the modern scientific enterprise. I might also point out that this is one of the areas where philosophy can really help us scientists think more clearly about what, in fact, we mean when we talk about gaining scientific knowledge, and how we come about that knowledge.
What do you think?
P.S., I also made a comment on the blog summary of the podcast that gave some specific contemporary examples of the interplay of theory and observation/experiment, if anyone is interested.