Philosophy

is the art of wondering about stuff.   Usually stuff that doesn't matter at all, and which no-one cares about.  Like science, the history of philosphy is replete with egregious error.  But where science makes progress (getting progressively less wrong as time goes on), philosophy just goes round and round in circles, repeating the errors but using new words (very cunning).  

Philosophy was invented by Plato a couple of thousand years ago (let's just ignore the Vedas and Upanishads for the moment).  He had a few mates who were really clever, but could not apply themselves and get a proper job.  So he set up a university where these clever but useless individuals could ply their trade.  An important part of this was inventing words.   The rationale was that the more new words they learned, the more others outside the university would be baffled by the bullshit, and awestruck by the perceived cleverness of the bods using those words.  To be completely fair to Plato, though, his stuff is much easier to read than most.   

Over the years there have been plenty of chaps willing to take the 'bullshit baton' and run with it.  My personal favourite is Heidegger, who employed the cunning use of hyphens to invent really great words (please research on the interweb, at your convenience).

Of course, philosophy was the foundation of all knowledge.  In due course other disciplines grew from it, and became proper intellectual pursuits, like the natural sciences, for example, and what we have left after this distillation process, is the ullage, the crap.  This is what modern philosophy (mostly) is.

There are two branches of modern philosophy - analytic and continental.  Analytic philosphy is the handmaiden of science, and involves using big words to try and make itself seem in some way important, useful or relevant.  Continental philosophy means German philosophy.  The main protagonists are Nietzsche and Heidegger, the first of whom has been pilloried as a proto-Nazi, and the second who was chucked out of the Nazi party 'cos he was a bit too scary for them...  Outside Germany, have a go at  Kierkegaard.  He is brilliant.  His idea was that philosophy was bullshit, and you should just stop going round in circles wondering about crap, and commit to something (in his case, God).  Continental philosophy boils down to these simple messages:

1    Wake up! (Nietzsche);

2   Be 'authentic' (Heidegger);

3   DO something (Kierkegaard)

In this respect, continental philosophy is infinitely superior to analytic philosophy - there is something useful you can take from it.

Logic

Well, we all like to think we are logical, don't we?  Logic is a good thing, right?  Errr no!  Basically, logic is a bunch of man-made rules to try and regulate and explain the world using various techniques. Essentially, logic is all in the mind, and ignores the real outside world, and tedious crap like, well, evidence.

Logic is not a part of science or allied to it.  It is the very opposite of science.  Logic, for example, dictates that a big thing will fall from a given height faster than a small thing.  The scientific method (invented by a Brit, of course - William GIlbert - not Gaileo who came a few years later (6 I think)) says:  "Bugger what ought to be the case, I am just gonna get a big thing and a small thing, drop them from the same height, and SEE which hits the deck first.  THEN, I'm gonna do it again and again and again, and record my findings.  Then, I'm gonna get other people to give it a go, and see what they find out too.  

Science is based on observation and evidence.  Logic is based on assumption - and as we know 'assume' makes an 'ass' out of 'u' and 'me'.

Circular Argument

A circular argument is one where the evidence that supports an argument is the argument itself.  This is best demonstrated by this, from Cathcart and Klein:

A native American goes off to get an education at Yale.  He is to be the next chief of the tribe.  But he goes of to college before he has had a chance to be educated in native American lore and customs.  He comes back from Yale and is the chief of the tribe.  The tribe ask him what kind of winter they are going to have.  He doesn't know, and guesses - 'I think it's going to be pretty bad' he says.  So the tribe gather wood.  He feels worried about his prediction and calls the weather centre and asks what the winter is going to be like.  He is told 'I think it's going to be pretty bad'.  He feels more confident and is asked again by the tribe.  Again he replies 'Yup, it's gonna be a bad one'.  They gather ever more wood.  Again he starts to feel shakey about his prediction and calls the weather centre, where he is told 'you know, I think it's going to be one of the worst winters on record'.  The chief feels buouyed up by this, but asks the weather guy 'Oh really?  But why do you say that?'  The weatherman replies 'well, the native Americans are gathering wood like crazy'....

I'll post some more on this subject in due course, if I can be arsed...In the meantime, have a look at the forum - contribute if you wish...