The following was posted on PZ’s blog, Pharyngula, in response to this entry: http://scienceblogs.com/pharyngula/2009/10/nicholas_wade_flails_at_the_ph.php
Evolution. Theory, fact, or both? I don’t think answering these questions is as simple as PZ or Wade make it seem. It involves more than science and philosophy, and forces us to deconstruct notions of a pure science uncontaminated by politics, culture, industry, and the happenstance of history.
“Fact” comes from the Latin, “facere,” meaning “to do,” or “to make.” In this sense, technoscientific facts are constructed not only by what scientific heroes do in the laboratory, but by the larger socioeconomic context determining which questions are worth asking and which research programs provide the best opportunity for investment returns to shareholders. The production and protection of facts costs money. If someone wishes to contest a fact, it also costs money to set up a counter-laboratory. Take a look at Bruno Latour’s book, “Science in Action” if you’re interested in how scientists and their networks of human and nonhuman allies construct facts.
As for theory, it is difficult to know where to start. Perhaps with PZ’s statement that theories “integrate a collection of facts into a useful model in our brains.” It is difficult to articulate how mysterious the work of theory is precisely because we must already have assumed a theoretical background to say anything at all about the world. Contrary to PZ’s assumption that facts pre-exist theories, I’d argue that the theory (or paradigm) within which one operates determines what counts as a fact. This is only partially true of course, because scientists inevitably begin to notice after a while the unexplained “noise” which builds up around a once favored theory. Given enough world-class scientific experimentation, the history of science clearly shows that revolutions occur and theories collapse, leading to gestalt shifts in the way scientists perceive the world (see Kuhn, 1962). What was once the highest and most authoritative scientific fact can come to seem in a single generation to be the silliest sort of pseudoscientific superstition. Theories change everything, even facts.
This is not a metaphysical claim about reality. I’m not saying human theoretical frameworks literally create nature. I am making phenomenological claim by saying that in every attempt to know the world, the world changes us as we change it. Knowing is not passive observation, but active participation.
So… evolution. Fact, theory, or both? I’d say both. But there is a history behind the word “evolution” which makes it a problematic choice in this context. As much as I’d like to get into the various reasons Darwin refused to use the word anywhere in “Origin of Species” (until he entered it once in the 6th edition), for lack of time I’ll just sum up: There are many evolutionary facts (like the genetic unity of all life), just as there are many evolutionary paradigms (neo-Darwinian, DST, Teilhard, Aurobindo, etc).