Ian Hacking, in his very readable book Representing and Intervening , describes an experiment done by a friend which involved changing the electrical charge on a minuscule ball of niobium. And how was that done, he asked? His friend said "Well, we spray it with positrons to increase the charge or with electrons to decrease the charge". And Hacking comments "From that that day forth, I've been a scientific realist. So far as I'm concerned, if you can spray them then they are real ." Hacking's story remind us that many of our best theories about "unobservables" enable us to do a lot more than reliably predict observable behaviour in a hands-off, watching-from-the-sidelines, sort of way. They do more than merely tell us a story about a supposed hidden substructure of the world, something that we could perhaps treat as a "just so" story, a useful fiction, a "heuristic". Our theories guide us in causally manipulating unobservables, and in causally producing desired observable effects. We can...

Well, Jake, it is flattering that you put the philosophers on this site on the same level as the famous philosophers of the past! But I don't think we quite deserve that . And maybe, indeed, what separates us from those all-time greats is some quality of mind that we're never going to acquire, however hard we work -- something innate, if you like. But let's not worry about trying to emulate the great: let's take your question to be one about how to get modestly competent at philosophy (like your average philosophy professor here). The short answer is: by reading, and thinking, and discussing. A lot. It is no good reading without thinking hard about what you are reading, trying your best to understand and critically evaluate the arguments as you go. It is no good just thinking without reading, or you will almost inevitably just re-invent various tempting views that are now well known to be horribly problematic: you need all the help you can get to avoid the pitfalls. And even if you read and...

Philosophy departments like to tell themselves (and their funding bodies!) that the study of philosophy distinctively makes their students better all-round thinkers -- in the fashionable jargon, our courses deliver special "transferable skills". Actually, that strikes me as really a rather unlikely claim (at least if it means any more than that our students grow up, get more mature, learn not to jump to conclusions, learn how to write well-presented coherently organized papers, etc., which happens with pretty much any serious academically rigorous degree course). Anyone who has sat through scores of departmental meetings, listening to various bunches of philosophers trying to muddle through organizing their affairs, often making a complete hash of it, knows perfectly well that -- outside their research work -- even the best philosophers are no better at thinking straight and keeping their eye on the ball than anyone else. (And after those departmental meetings, are the pub conversations about...

"Burden tennis", batting the burden of proof to and fro over the net, is rarely a very profitable pastime! But still, maybe this case is an exception. After all, conventional theists when you come down to it are making some pretty exotic claims (claims that make the beliefs, say, of ancient Greek religion look very modest and humdrum). Not just powerful gods, but an omnipotent God. Not just intermittently casting an amused eye over mortal folly, but omniscient . Not just occasionally taking a passing interest in some of us, for good or ill (and occasionally, understandably, running off with a particularly pretty nymph) but incomprehensibly loving us all equally . And so it goes (for example, perhaps add claims about the Trinity here!). By the workaday epistemic standards we use in most of our lives, those extravagant claims look very fanciful indeed. So we can reasonably insist that someone who advances such claims literally, and expects to be taken seriously, had better have some ...

I can't agree that it sounds a cool class. Indeed, if this is going on in a school or college, it is an intellectual disgrace. "Teachings" of any kind are only worth the arguments that support them: and refusal to engage in critical argument by their proponents deprives the teachings of any call on our respect. Sure, if this is an extra-curricular, non-school, class that you are finding culturally interesting or emotionally satisfying, carry on with it. Get what you can out of it. But whatever is going on doesn't sound like philosophy to me.

Take a law-statement of the form "All A s are B s" (I'm not saying that every law-statement has to be of this form: but it will do no harm to concentrate on this type of case). Then we can ask a pair of related questions. First, what kind of fact(s) make this type of law-statement true ? For if the statement isn't even true, it certainly isn't a law. And we can ask, second, what makes the statement a law -statement . For not all true generalizations are laws: some are just accidentally true. Different philosophers offer different package answers to this pair of questions, and the issues here are very hotly contended. It would be difficult to say much about them here, and we'll have to shelve any extended discussion. But let's see if we can make just a few preliminary comments relevant to the question originally posed. First: note that sometimes when people talk about laws they mean law-statements; sometimes when people talk about laws they mean the facts that make the law...

To start with a story. Once upon a time, I used to teach introductory logic using Lemmon's textbook. And some exam questions would have the form "Use truth-tables to test the following arguments for validity; in the cases where the argument is valid, provide a proof from the premisses to the conclusion in Lemmon's system". Given that Lemmon's natural deduction system is complete, a student who correctly did a truth-table showing that a particular argument is valid thereby proved that there is a proof from the premisses to the conclusion. But of course, she had to do more to answer the second part of the question, and get the marks! She had to give an actual natural deduction proof. This little story reminds us that, quite often, we aren't just looking for any old proof, but for a proof of a certain style S , a proof that uses certain kinds of resources. And proving that an S -proof of some result exists isn't in general to give an S -proof. This sort of point applies outside the...

At any one time, quite a bit of science is provisional, conjectural, and the subject of hot debate among scientists. So, rather boringly, science in general can't be said to be a system of " universally codified opinion". I suspect, however, that the intended question is something more like this. Take a scientific claim that isn't any longer provisional, conjectural and contested -- e.g. take the claim that DNA has a double-helix structure. Then, the rephrased question goes, does this claim in any good sense tell us the fact of the matter, tell us how the world is independently of us? Or is it, in the end, merely that some bunch of people (the scientists) have come to a shared opinion about the world, in this case the opinion that DNA has a double-helix structure? To which the common-sense realist answer is the first. After all, science tells us, it is the fact that DNA does indeed have a double-helix structure which causally explains the behaviour of DNA under...