Kingsley Amis came up with that rather cynical little verse and it's been rattling round in my skull for many years. It's an old syllogism, whether we phrase it in verse or in prose, and it reflects a mind set that is unfortunately still all too common. SF is obviously trash, therefore anything that is not trash cannot possibly be SF, even if it is full of SF trappings.

I suppose that's why Kurt Vonnegut, a well respected mainstream writer whose works have always been claimed by the SF world, was more than a little grumpy about being tarred with the SF brush. "I have been a soreheaded occupant of a file drawer labelled science fiction…", he said in an essay in his collection Wampeters, Foma & Granfalloons, "and I would like out, particularly since so many serious critics regularly mistake the drawer for a urinal."

But Vonnegut was a well known curmudgeon and professional cynic. Other writers have different opinions about the subject. Michael Chabon is a mainstream writer who has been heaped with praise by the critics. He has won countless literary awards. Each new Michael Chabon novel is always eagerly anticipated in the literary journals.

Then, in 2008, Chabon won a Hugo award for his novel The Yiddish Policeman's Union. And just to prove it wasn't a fluke, the same novel went on to garner a Nebula award, a Locus award, a Sidewise award (whatever that is) and it was also short listed for a British Science Fiction Association award. Shock, horror!

Chabon himself was quite unfazed by the fuss that this caused. He freely admits that most of his novels contain SF themes and references (he probably had a misspent youth reading SF books under the bed covers by torchlight). In interviews, Chabon has never denied that what he writes can easily be interpreted as SF. He has always said that he was very proud to have won his Hugo award and, shortly after winning it, he affirmed his close ties with the SF world by joining the Science Fiction Writers Of America (SFWA).

So who is correct? Is Vonnegut correct when he says he doesn't write SF? Is Chabon correct when he says that he does? And are the snobbish mainstream critics correct if they claim that neither author writes SF because obviously their books are far too good to be stigmatized by attaching that derogatory label to them?

I'll agree very strongly with the last point. The books that Vonnegut and Chabon write are definitely genuine works of art. But after that I'm honestly uncertain what comes next. It's that very old problem of definition again. What is SF? Can something be called SF just because it contains SF tropes? Can it be SF if it doesn't contain these things? Can something that is full to the brim with SF ideas ever be considered not to be SF? None of these questions have easy answers.

Some friends of mine are currently embroiled in a fatuous debate about whether or not a particular work is SF. Indeed, some of them are even going to the ridiculous extreme of trying to define just how much of the work is SF – 50%, 60% or only 30%?

It's all complete and utter nonsense. You can't estimate the proportion of SF in a work if you can't even define SF in the first place. And, believe me, you really cannot define SF. People have been trying to define the genre for 83 years (as of 2009), to my sure and certain knowledge, and no conclusion has ever been reached. The debate is just as sterile now as it was back then, but it continues to be argued just as fiercely.

So the hell with it all! Let's have some fun with the idea. There aren't any rules that say we have to be serious all the time. Consider this:

There's currently an advert on TV for a kitchen cleaner. The advert shows an immaculately dressed young woman casually wiping a cloth over grease and yucky bits supposedly baked on to an oven surface. The cloth skims lightly over the crud, leaving the areas where it has wiped fresh and gleaming. The young lady never breaks into a sweat and gets not an atom of muck on her. As anybody who has ever tried to clean an oven knows, this never happens in real life. Lots of scrubbing is required; it's a filthy, horrible job. The advert is obviously fantasy of the highest order. I think I'll nominate it for an award.

(For the humour-impaired among you, let me just point out that I know that I've suddenly started treating the terms SF and Fantasy as synonyms. That's because I want to, and you can't stop me. So there. Nyaah! Nyaah! Nyaah!)

Now let's look elsewhere. What about that very famous, multi-award winning SF film and book Dune by Frank Herbert?

Well, it's quite clear to me that Dune is not even tangentially SF and it should never have been considered for an award. The Fremen are obviously only thinly disguised Arabs and the desert world of Dune is itself simply a metaphor for the Middle East. Indeed, Paul Muad D'Ib himself is quite obviously a symbol for the house of Ib'n Saud (the similarity of the spelling gives it all away). Given his position as the leader of a revolutionary movement (some might call him a terrorist, others a freedom fighter) it is obvious that Paul is being equated with Osama bin Laden, himself a member of the house of Saud. Dune therefore, is nothing but a commentary on the politics and religions of the Middle East as they intersect with their Western equivalents. All the so-called science fictional trappings are merely allegorical and metaphorical literary devices designed to shore up this intellectual structure.

So there's absolutely nothing science fictional at all about Dune. Let's start a movement to have its awards stripped from it...

See how easy the game is? And how much fun?

How about if we turn the problem on its head and start with some rigid definitions of the genre instead? Let's pretend that we really can define SF. Surely if we can pin the genre down before we begin to look at specific examples we will have a much easier time trying to decide whether or not the advert and the novel that I just discussed really are SF, won't we?

Well no – doing it that way actually opens up a whole new can of worms. Or perhaps, given my less than reverent attitude towards the subject, a completely different barrel of laughs. The argument goes like this:

Margaret Atwood is a mainstream writer who finds herself in much the same position as Kurt Vonnegut and Michael Chabon. She has written several novels that many people consider to be science fiction. But she herself denies that charge vehemently. She has resolved the paradox in a very clever way – she has completely redefined science fiction in such a way as to remove her novels from consideration.

Science Fiction, according to Margaret Atwood, consists of stories about talking squids in outer space. Since there are no talking squids in her novels, her novels cannot possibly be science fiction. QED.

Actually, I really like this definition. Since I don't recall ever reading or seeing anything with talking squids from outer space in it, it becomes clear to me that no science fiction stories at all have yet been written by anyone. (Charles Stross got very close in Accelerando – but let's face it, lobsters aren't squids. Nice try, Charlie, but no banana). I am now eagerly awaiting the first ever proper science fiction story to reach the world. Whoever writes it will make a fortune! They will have invented a whole new genre…

Anyway, at least now we can state with some certainty that nothing written by Kurt Vonnegut, Michael Chabon or Margaret Atwood is science fiction. No talking squids.

Or look at it another way. It's pretty much axiomatic that science fiction stories can be set in a time and place before the universe even existed; they can be set after the universe has been destroyed; and they can be set at any time and place between these two extremes. That thing which we call mainstream literature must, by its very nature, take place completely inside a very narrow band that is itself completely contained within this huge spectrum. Therefore it is perfectly logical and perfectly reasonable to claim that ALL literature is actually science fiction, and the so-called mainstream is just a special case of that broader category. Mainstream literature is SF stripped down to the bare essentials, if you like.

Consequently we can now state with some certainty that everything written by Kurt Vonnegut, Michael Chabon and Margaret Atwood is science fiction. Who needs talking squids?

The white queen could believe six impossible things before breakfast. I have much easier task. I only have to believe the very Zen-like paradox that every piece of fiction ever produced by anybody both is, and is not, science fiction simultaneously. Simple, really!

If these silly games prove anything, they prove that SF wriggles when you poke it. It never stands still; it never stands up to be counted. Everything is science fiction and nothing is science fiction. Except when there's a 'Q' in the month. Or possibly when there's a number in the year.

It's all far too easy and it's all far too ridiculous. The discussion currently going on among my friends was doomed to failure before it even began.

How many SF writers can dance on the head of a pin?

So have I been reading any SF this month? Well, obviously everything I've been reading is SF. Or, equally obviously, nothing I've been reading is SF. Both statements are equally true, so I really don't mind which one you prefer...

Fool is the new novel by Christopher Moore, a novelist high on my list of writers whose books I buy in hard cover as soon as they are published. Unfortunately I found myself a little disappointed with Fool. One of the major attractions of Christopher Moore's work is the raving lunacy of his plots. He seldom lets little things like plausibility get in the way of a good story and his novels tend to be stuffed full of vampires, lust-crazed creatures from the vasty deep, sentient fruit bats, demons with a hellish sense of the absurd, and similar insanities. Fool contains none of these things (well, it does have some witches, but so do a lot of other books). Because the novel is relatively pedestrian in comparison to his other stories, the humour never quite works in the way he intends it to.

It also doesn't help that Moore has chosen to write a novelization of King Lear and he tells the story from the point of view of the fool, one of Shakespeare's least funny and least insightful characters. Don't get me wrong, I'm a huge admirer of Shakespeare and, if you choose your passages with care, he is not without humour. A good production of a funny play can still make a modern audience roar with mirth. But Lear is not one of those plays (well, it is a tragedy after all). There's not a lot of laughs in the degeneration of a senile old man being taken advantage of by his scheming daughters. I suspect Shakespeare intended the fool to serve as a counterpoint to the more harrowing passages, introducing some light relief into what would otherwise be a never ending slough of despond. Perhaps it worked 400 years ago, but it certainly doesn't work today. The fool remains determinedly unfunny to modern ears ("Marry nuncle...").

Moore does his best. He doesn't stick rigidly to the Bard's story and he throws a lot of other Shakespearean stuff into the plot – we get Macbeth's witches (and highly entertaining they are as well) and Birnam Wood goes walkabout of course. There's lots and lots of this and it's always fun to play 'spot the reference' of course. But, in the final analysis, none of it manages to transcend the obscure dullness of the fool himself. Moore tries very hard, but paradoxically I feel that he's captured the Shakespearean essentials of the character far too well, and the fool continues to spout oddly incomprehensible 'jokes' as he manoeuvres his way through complex political machinations that hover right on the edge of making sense, but never quite manage to do so.

Allen Steele has come up with a couple of books this month. The Last Science Fiction Writer (lovely title) is a collection of short stories published by Subterranean Press in a very limited edition of only 1000 copies. So you aren't going to see it on the shelves in your local book store any time soon, I'm afraid. Indeed I strongly suspect it's already sold out, and Subterranean Press are often reluctant to reprint their limited editions in case it lowers the value of the first print run. And that's a shame because the stories in the book are really quite good. Mostly he revisits his own trademarked universes, so we have some near space stories and a Coyote story (this last, The War Of Dogs And Boids has obviously been typeset from the original magazine publication without any copy editing at all – it is so riddled with typos that it becomes almost unreadable. I'm surprised Steele didn't pick it up in the galleys. Maybe he only pretended to read the galleys.)

However Steele's other publication this month is a new novel from Ace. Although it's only currently available in hardback, I'm sure it won't be long before a paperback edition appears. Coyote Horizon is another episode in the seemingly open ended series that Steele has been writing for the last ten years or so. I suppose it is possible to read the book in isolation, without any knowledge of what has gone before, but you will get a lot more out of it if you have read the earlier books.

He's had a mixed reception from the critics for his Coyote novels, but I've always enjoyed them and Coyote Horizon is no exception. I found it an excellent read.

The basic scenario of the series is that colonists from Earth are living on a recently discovered extra-Solar planet called Coyote. Thirty years ago, such a plot would have unwound itself in lots of exciting adventures as the colonists explored the planet and interacted with strange new life forms and discovered lots of weird and wonderful things as they boldly went. Allen Steele does indeed do a little of this – mainly, I suspect, in order to generate the appropriate science fictional atmosphere and to give a certain feeling of realism to the world in which his stories take place. But he never uses it as an end in itself. Quite rightly, in my opinion, he seems to believe that such an exploration can no longer be the major focus of a modern SF novel because it's been done to death too many times in the past by too many other writers. Instead he uses the scenario to explore the ramifications of various political, social and (in the case of Coyote Horizon) religious and philosophical ideas. The pioneer society on Coyote is pitted against older, more entrenched, less flexible societies on Earth and also (in the later books) against utterly alien societies from elsewhere in the galaxy. There are major lessons to be learned from the comparisons.

This approach gives him a lot of room to manoeuvre and let's face it, these are exactly the reasons why writers as diverse as H. G. Wells, George Orwell, Aldous Huxley and Anthony Burgess et al chose the SF genre to explore their ideas. Allen Steele is standing on the shoulders of giants.

Unfortunately Steele himself is a deeply conservative man who is firmly convinced that there is only one right way to do anything, and that way is the American way. He's almost absurdly patriotic (I'm not making this up – he's said it quite explicitly in several published essays) and these attitudes obviously load the dice that he throws for his plots. As a consequence, a certain naivety is sometimes apparent in his concerns.

He's not a stupid man and, anathema though his views may be to non-American non-conservatives such as me, he nevertheless makes an honest attempt to present convincing cases. I believe his premises are flawed and his conclusions suspect (particularly as far as the society that develops on Coyote itself), but that doesn't stop me enjoying the scenarios that he explores. He's a skilful and persuasive writer whose work I greatly admire. I buy his books in hard cover, and that in itself speaks volumes about my admiration for his work.

Steele's ingrained Americanism and his sometimes profound ignorance of the way the world works outside America occasionally leads him into infelicities of expression. There's a beast of burden on Coyote which is called a shag. Well that's fair enough, I suppose. After all there's a bird on Earth which is also called a shag. He's allowed to use the name. But then he hitches his shags up to various vehicles that the colonists drive around in. And every time one of these vehicles appears in the story he calls it a shag wagon. And every time I read those words I giggle, and the spell of the story breaks for a moment. It's quite clear to me that Allen Steele knows nothing about English slang (or perhaps he just doesn't have a dirty mind.) Oh well, I suppose we can forgive such a minor peccadillo.

It's been two years or more since Lindsey Davis last published a novel. She has claimed in various interviews that she wanted to take her time; she didn't want to feel rushed or pressured into writing the next novel in her ongoing series about Falco, the private detective (or informer, as he calls himself) in Vespasian's Rome.

That's all well and good, and I for one certainly don't begrudge her the time she has taken to polish her prose and hone the sharp edges of her plot. But honestly I can't see any real difference between her other novels and this one. The quality of her writing and plotting has always been consistently very high even if she herself felt that the pressure to produce had forced her to publish before she was ready. I certainly never saw any evidence of this in her earlier works and neither do I see any evidence that her new novel, Alexandria is of any higher quality than those books that preceded it. It's just another Falco novel and as always the plotting is tight, the writing is brilliantly evocative and often very funny, and the characters spring fully to life as they leap out from the page at you and grab you by the throat, demanding that you listen to their story.

Falco is on holiday. He and his wife Helena Justina are collecting the seven wonders of the world. Helena Justina is eager to see them all before the next baby (which is due at any minute) ties her down to hearth and home for the foreseeable future. And so they go to Alexandria to see the lighthouse and the famous library and it isn't long before Falco stumbles across several corpses and discovers a foul conspiracy involving library management practices (lots of wonderful jokes here), corruption, illegal autopsies, a man-eating crocodile, and the sale of stolen manuscripts...

It's a Falco novel. It has something for everyone. What more is there to say? I loved it and so will you.

There's a myth abroad among Tim Dorsey fans that his even numbered novels are pretty good, but his odd numbered novels are a blast. Nuclear Jellyfish is novel number eleven so I was expecting great things, and I wasn't disappointed. I think it's his best one yet.

We're back with Serge A. Storms, the psychotic, obsessive-compulsive, homicidal maniac who roams the length and breadth of Florida immersing himself in its history and culture and telling his perpetually drunk and perpetually high sidekick Coleman all about it.

The book opens with Serge and Coleman staking out a bridge and discussing Lynyrd Skynyrd. It soon becomes clear that they are both wearing diapers (nappies for us English speakers) in fond memory of Serge's favourite lunatic astronaut who travelled by car across Florida (and much of the rest of the country) intent on murdering her unfaithful lover, and who didn't want to be distracted from her sinister purpose by bathroom breaks.

Serge has decided to launch his own Travel Guide Blog to Florida, featuring handy survival tips for the Floridian Tourist. This quest has him criss-crossing the state in search of iconic landmarks that he can photograph and post to his (somewhat eccentrically bewildering) blog. Many of these landmarks seem to involve Lynyrd Skynyrd.

Along the way, Serge and Coleman pick up a hitch hiking exotic dancer (call her a stripper and she gets violent) who is on a mission of vengeance. Serge immediately falls in love with her – she knows more about Florida history than he does! This guarantees that their frantic couplings lead him to the ultimate orgasm. He chants extensively detailed Floridian lists while in the throes of passion.

Meanwhile there's a whole slew of diamond smuggling coin collectors to deal with as well as the evil genius behind the bad guys who proves to be a blood-thirsty sociopath with a strangely formed glow-in-the-dark tattoo on his chest. It might be a jellyfish (hence his nickname among his henchmen). He however considers the tattoo to be an eel and prefers to be so addressed. Underlings who refer to him as Jellyfish tend to get dismembered.

And while all this is going on Serge, as always, allows himself to be distracted from his main purpose in order to dispose of various villains who upset him with their ignorance, their rudeness and their anti-social attitudes. Using freely available domestic supplies (particularly duct tape) purchased from his favourite hardware store (Home Depot), Serge constructs deadly Heath Robinson devices that guarantee a high death-toll, an amusing assortment of severed limbs and stuff that goes bang!

In short, it's the usual utterly insane mixture as before, and Dorsey has never done it better.

Just to complete the reading list, I've also been on a massive binge of Sue Grafton's so-called alphabet novels. They are fairly traditional private-eye stories featuring one Kinsey Millhone. She's in her mid-thirties, an orphan, twice divorced and living alone. All the novels have titles such as: A is for Alibi and B is for Burglar etc. So far, Sue Grafton has written her way up to the letter T and I've read all the way up to R. The series will probably be finished in about four more years.

In a sense they are routine private eye books, and there certainly is a degree of formulaic writing and plotting to the series. That's probably only to be expected in a 26 book series. But Sue Grafton does try very hard to transcend the genre and avoid the formalisms and by and large she succeeds. Kinsey herself is always a fascinating person and I find myself more and more interested in just how she is going to come to terms with some of the ongoing pressures in her life.

The plots are sometimes prosaic (and sometimes magnificently clever; you never can tell which will be which – just read the books and make your own mind up) but I've always found Kinsey herself sufficiently well realised to keep me reading and leave me eager for more. If you like books like these, you'll love these books. I certainly do.