Through my classes on the history of 20th century physics and the philosophy of Nietzsche, it has become ever more apparent to me that physical theories are really a kind of art. This is to say that even in physics-- a field which purports to reveal the truth of the nature of the universe-- there is choice in constructing our theories and interpretations. These choices are not made based upon what is "real", but on aesthetics.
This realization is something that I have oft resisted, because the possitivist viewpoint which governs most physicists' thinking attempts to ground our theories in an external, measurable, truth. Yet, I am coming now to reconsider some of these conceptions. This is not to say that I now doubt the existance of truth, but rather that I now realize that the point of the scientific method is not that reproducibility ensures truth. Instead, reproducibility gives us a measure of confidence in experimental results. In the end, there is no certainty of any result, because researchers many years from now may discover a fatal flaw in our experiments.
Yet, there is still value in the possivist viewpoint, because at some point we need to posit the existence of facts in order to develop new theories and progress to new, better, more accurate ideas.