This is part three of my origins debate series. Part one, part two.
With definitions of MethN and MetaN in hand, I'm going to argue that only MethN can be rightly called science. MethN is both the foundation and limits of a systematic study of the natural world.
MethN is a particular view of epistemology - a theory of knowledge. Now, I don't think MethN can form an epistemology all by itself. It is too limited; if one uses MethN has the basis of all knowledge, it quickly becomes either MetaN or a half-assed reaction against MetaN.
In the strictest sense, as I said in this post, we have no undoubtably firm foundation for knowledge. MethN, however, does not require such a starting point. Generations ago, David Hume questioned any possibility of science when he said we have no grounds to believe in uniformity. That is, Hume pointed out that we cannot make the unquestionable and dogmatic statement that even though X has always led to Y, it will not necassarily do so again in the future. For example, we cannot be without doubt that the sun will rise tommorow.
That might sound unecassarily silly or anal or trivial, but it's been a serious poin of contention. To my knowledge, Karl Popper - writing in the 1940s - offered the best rejoinder to Hume. Popper offered the standard of falsifiability. That is to say, in order for a statement to be considered as science, it must be falsifiable.
That is bound up in the scientific method itself. Offer a hypothesis, test the hypothesis. Here is the kicker, and the limit of MethN: in the strictest sense, following Hume and Popper, science does not prove anything. Science is incapable of proving that X is true - it can only ever prove that X is untrue.
When we say X is "scientifically true," what we are really saying is that X has been systematically tested, and has not been falsified. A scientific law is is a concept that has been repeatedly and thoroughly tested, and has never been falsified - gravity, for instance. This is also why we trust our technology to work as expected; we get on an airplane, because we know that the principles at work have been tested millions of times over, and never falsified (mechanical failures are a different issue).
Falsifiability is the epistemological core of MethN. It is the line that is crossed when one enters into MetaN or any other metaphysical framework. When one attempts science without this guideline, any possibility of explaining the success of science falls away. We return to a Humian skepticism, and all scientific research will become deaf, dumb and blind. This effect provides a definition for the talismanic phrase "anti-science." To be anti-science is to leave behind MethN, and yet to insist that you are within the bounds of science. To be anti-science is to throw a monkey wrench into the scientific method; it is to be a hypocrite in our technological world, and it is to have a worldview that cannot incorporate centuries of scientific research.
How does this relate to the origins debate? I think many on both sides constantly leave behind MethN, while insisting they have remained within the bounds of science. I believe the MetaNer who does not acknowledge the distinction between MetaN and MethN is anti-science, and I believe the SYECer is anti-science in a similar way.
An example from both sides. Carl Sagan was a committed metaphysical naturalist. He took a dim view of all supernatural concepts; for example, he wrote a book called The Demon-Haunted World: Science as a Candle in the Dark. I haven't read that, but I have read his Cosmos and Broca's Brain. Sagan was probably the greatest popularizer of science of all time; he was charismatic and an excellent educator. He had a tv show, and appeared on The Tonight Show countless times.
He was a scientist of some professional reputation, as well. This means he had a fine grasp on MethN, and used it to all of our benefit.
However, I do not believe he drew a sufficient line between his MethN-guided work, and his MetaN-based beliefs. In practice, Sagan was an excellent scientist. In his philosophy, I believe his lack of interest - or ability to - draw a line between MethN and MetaN resulted in an anti-science contradiction.
It is not that his MetaN beliefs were ungrounded or unjustified. The problem is that Sagan often expressed MetaN views while speaking as a scientist. When one speaks as a scientist, they must limit themselves to what is uncovered by MethN - or engage in a contradiction that threatens the foundation of science.
I repeated myself a few times there; that's because I don't think i was entirely clear. Hopefully quantity will clarify what quality has obscured. I'll talk about SYECers next time.