On the difference between science and philosophy

By Massimo Pigliucci

Take, for instance, my recurring argument that some (but not all!) of the “new atheists” engage in scientistic attitudes by overplaying the epistemological power of science while downplaying (or even simply negating) the notion that science fundamentally depends on non-empirical (i.e., philosophical) assumptions to even get started. Since my personal career, first as a scientist for 27 years, now as a philosopher, has been marked by experience in both fields, and moreover by a strong belief that the two enterprises are complementary and not adversarial, I feel it is time to make some extended comment on this general issue.

It is perhaps appropriate to tackle the problem at the end of 2009, the year that marks not just the 150th anniversary of Charles Darwin’s Origin of Species (and the 150th anniversary of the publication of the arguably even more momentous On Liberty by John Stuart Mill), but also the 50th anniversary of C.P. Snow’s famous essay “on the two cultures,” on the intellectual divide between the sciences and the humanities.

In his essay, Snow (rightly) chastised what he saw as an unjustifiable attitude of intellectual superiority on the part of people from the humanities’ side of the divide: “A good many times I have been present at gatherings of people who, by the standards of the traditional culture, are thought highly educated and who have with considerable gusto been expressing their incredulity at the illiteracy of scientists. Once or twice I have been provoked and have asked the company how many of them could describe the Second Law of Thermodynamics. The response was cold: it was also negative. Yet I was asking something which is the scientific equivalent of: Have you read a work of Shakespeare's?” Indeed, it ought to be indefensible that someone is considered ignorant for not having read Shakespeare, and yet the same charge is unthinkable when it comes to fundamental scientific concepts, like the second principle of thermodynamics.

But the problem cuts equally deeply on the other side, just consider the following quote from physicist Steven Weinberg (in his Dreams of a Final Theory): “The insights of philosophers have occasionally benefited physicists, but generally in a negative fashion—by protecting them from the preconceptions of other philosophers ... Philosophy of science at its best seems to me a pleasing gloss on the history and discoveries of science.” Here Weinberg makes the all-too common mistake of thinking of philosophy as of an activity whose entire worth is measured by how useful it is to solve scientific problems. But why should that be so? We already have science to help us solve scientific problems, philosophy does something else by using different tools, so why compare apples and oranges? By the same token, why not ask why art critics don’t produce paintings, for instance, or editors write books?

For the purposes of this discussion, I assume that most people have at least some idea of what science is, if not of the intricacies of the epistemological and metaphysical problems inherent in the practice of science (and there are many: as Daniel Dennett put it in Darwin’s Dangerous Idea, “There is no such thing as philosophy-free science; there is only science whose philosophical baggage is taken on board without examination.”) Science, broadly speaking, deals with the study and understanding of natural phenomena, and is concerned with empirically (i.e., either observationally or experimentally) testable hypotheses advanced to account for those phenomena.

Philosophy, on the other hand, is much harder to define. Broadly speaking, it can be thought of as an activity that uses reason to explore issues that include the nature of reality (metaphysics), the structure of rational thinking (logic), the limits of our understanding (epistemology), the meaning implied by our thoughts (philosophy of language), the nature of the moral good (ethics), the nature of beauty (aesthetics), and the inner workings of other disciplines (philosophy of science, philosophy of history, and a variety of other “philosophies of”). Philosophy does this by methods of analysis and questioning that include dialectics and logical argumentation.