Attentive readers of this blog may have noticed that those who post comments to my entries often show two interesting and complementary attitudes: a fundamental distrust of (if not downright contempt for) philosophy, coupled with an overly enthusiastic endorsement of science. 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.Now, it seems to me obvious, but apparently it needs to be stated that: a) philosophy and science are two distinct activities (at least nowadays, since science did start as a branch of philosophy called natural philosophy); b) they work by different methods (empirically-based hypothesis testing vs. reason-based logical analysis); and c) they inform each other in an inter-dependent fashion (science depends on philosophical assumptions that are outside the scope of empirical validation, but philosophical investigations should be informed by the best science available in a range of situations, from metaphysics to ethics and philosophy of mind).So when some commentators for instance defend the Dawkins- and Coyne-style (scientistic) take on atheism, i.e., that science can mount an attack on all religious beliefs, they are granting too much to science and too little to philosophy. Yes, science can empirically test specific religious claims (intercessory prayer, age of the earth, etc.), but the best objections against the concept of, say, an omnibenevolent and onmnipowerful god, are philosophical in nature (e.g., the argument from evil). Why, then, not admit that by far the most effective way to reject religious nonsense is bycombining science and philosophy, rather than trying to arrogate to either more epistemological power than each separate discipline actually possesses?Another common misconception is that philosophy, unlike science, doesn’t make progress. This is simply not true, unless one measures progress by the (scientific) standard of empirical discovery. But that would be like accusing the New York Yankees of never having won an NBA title: they can’t, they ain’t playing the same game. Philosophy makes progress because dialectical analysis generates compelling objections to a given position, which lead to either an improvement or the abandonment of said position, which is followed by more critical analysis of either the revised position or of the new one, and so on. For instance, ethical theories (moral philosophy), or theories about consciousness (philosophy of mind), or about the nature of science (philosophy of science), have steadily progressed so that no contemporary professional philosopher would consider herself a utilitarian in the original sense intended by Jeremy Bentham, or a Cartesian dualist, or a Popperian falsificationist — just in the same way in which no scientist today would defend Newtonian mechanics, or the original version of Darwin’s theory.It is also interesting to note that the process I just described may never reach and end result, but neither does science! Scientific theories are always tentative, and they are always either improved upon or abandoned in favor of new ones. So how come we are willing to live with uncertainty and constant revision in science, but demand some sort of definitive truth from philosophy?Now why is it that so many people take sides on a debate that doesn’t make much sense, rather than rejoice in what the human mind can achieve through the joint efforts of two of its most illustrious intellectual traditions? I think the answer here is no different from the one available to Snow fifty years ago: people in the humanities are afraid of cultural colonization (which is actually the expressed agenda of scientistic thinkers like E.O. Wilson, see his Consilience: The Unity of Knowledge), while scientists have been made arrogant by their recently acquired prestige and enhanced financial resources, so that they don't think they need to bother with activities that don’t bring in millions of dollars in funding every year.It’s a rather sad, and indeed positively irritating, state of affairs, which is being fought by a handful of activities (usually, though not always, initiated by philosophers), like my own “sci-phi” effort, or like the Permanent Observatory on Integration between the Human and Natural Sciences in Italy. It’s an uphill battle, especially in an era of ever increasing academic specialization, not to mention the ease with which people can now customize their intellectual experiences online, reading only the sort of things they are already interested in, or authors with whose positions they already agree. Which is actually one of the things that make this particular forum somewhat unusual and, to me at least, stimulating. So fire away your opinions, let the sci-phi discussion begin!