The reader is now in possession of all the facts needed to determine what has happened to the aliens , and I hope not to be pointing out the obvious if I explain that the clue is in the apparent speeding-up of their television broadcasts .sx They don't speed them up , which means , for instance , that when they walk around their space-ship they can change direction in something of the order of one-ten-thousandth of a second while moving at 30,000 miles an hour .sx No humanoid frame could stand that , unless its mass were very tiny .sx The aliens , then , are on the airfield all right , but their space-ship is sinking into a muddy heelprint or whatever .sx Apart from the effects of awe and amazement produced by the description of the pulpy monsters and so on , what we have here is a strong puzzle interest that is widespread in science fiction as a minor aspect and not uncommonly central , as in this case .sx I have already mentioned the biological puzzle- problems of determining an alien life-cycle and the like- as an important sub-category ; another involves the question of finding the weak point in some apparently invulnerable monster or hostile alien or badly behaved human artifact of the robot sort .sx The solutions to these may be progressively revealed rather than shown as deduceable , but they need not be , and " Pictures Don't Lie " is not an isolated example of the approach that offers what are valid clues , even if they are only seen as such in retrospect .sx Although interests of this kind can hardly be classed among the most lofty , it seems legitimate to call them as literary as any other .sx Certainly science fiction appears to be on the point of taking over some of the functions of the traditional detective story , currently I believe in grave disrepair , though with a large audience , in England at any rate , nurturing itself on reprints and the more problem-posing kind of thriller .sx I cannot believe that the Anglican parson and the Oxford classics don , those alleged archetypes of the Agatha Christie fan , would bring themselves to look through the files of Astounding Science Fiction in search of a story like Isaac Asimov's " Little Lost Robot , " but they would be the losers by their reluctance , for the science-fiction deduction problem , while to some tastes inferior to the detective story in its weaker connections with the world we know , is superior to that tiny motive-means-opportunity system in its range of both problems set and kinds of answer proposed .sx To take the commercial aspect :sx some partial merger between the publics of the two modes does seem eventually possible , as Anthony Boucher , the most level-headed of science-fiction commentators , foresaw some years ago .sx I have already mentioned the tendency of the more full-time writers to have a foot in both camps :sx Boucher himself doubles as the whodunit reviewer of the New York Times , and although I cannot personally confirm his assertion that science-fiction elements have recently become perceptible in some detective stories , the opposite process is clearly under way .sx A recent story by Poul Anderson , " The Martian Crown Jewels , " gives us a brilliantly clever and inventive synthesis of the two media , with a Martian detective called Syaloch who affects a tirstokr cap , a locked-space-ship problem , and a completely fair presentation of clues ingeniously disguised as technological patter .sx Even the most hardened Baker Street Irregular would be captivated by the story- if he ever learnt of its existence .sx Elsewhere , science fiction has been combined with what we are accustomed to distinguish as thriller or mystery ingredients rather than specifically deductive ones .sx All of these make some appearance in Chad Oliver's novel Shadows in the Sun .sx The problem here is why a small town in Texas consists entirely of recently arrived inhabitants and why these are all too average to be believable .sx This is soon explained- the hero boards a flying saucer on page 27- but the first three chapters are stuffed with 'tec tricks of presentation and style , from verbless sentences and sinister single-sentence paragraphs " He was afraid to go out " or " He had to " ) to the image of the hero , who is an anthropologist but tough- the ordinary science-fiction hero needs no such apology for his learning .sx This chap was a big man , standing a shade under six feet and pushing two hundred pounds .sx His brown eyes were shrewd and steady .sx He was dressed in the local uniform- khaki shirt and trousers , capped with a warped , wide-brimmed hat at one end and cowboy boots at the other .sx His Ph .sx D. didn't show , and he didn't look like the kind of a man who had often been frightened , and as you might expect he soon takes up with Cynthia , who although fresh off the flying saucer makes good Martinis and is cool and slim and sets the hero's stomach feeling tight .sx These are recognisable as importations into science fiction , which avoids that particular kind of cheap-jack stuff and indeed deserves a small round of applause for not trying to expand its audience by concessions to salacity .sx A less inane ( and more recent ) example of attempted hybridisation is Richard Matheson's A Stir of Echoes , described on the wrapper simply as " a novel of menace " but in fact fusing science-fiction and 'tec elements with some show of wholeheartedness to produce a murder mystery with telepathic clues .sx The ability of a literary mode to expand into others is often taken as a sign of vitality , and it is true that between them fantasy and science fiction have gobbled up most of what was left of the horror story without much injury , but I cannot feel that the injection of these thriller ingredients is likely to lead to much beyond blurring and dilution .sx It is not by capturing more territory that science fiction will improve itself , but by consolidating what it already has .sx Such internal reconstruction would do well to start with an attempt to bring sexual matters into better focus .sx Going easy on the puritanism would be a commendable resolve , and so would a decision to drop sex altogether where it is not essential rather than to decorate a planetary survey or alien invasion with a perfunctory love interest presented in terms borrowed from the tough school or the novelette .sx What will certainly not do is any notion of turning out a science-fiction love story .sx In the as yet unlikely event of this being well done , the science fiction part would be blotted out , reduced to irritating background noise- a dozen Venusian swamp-lilies being delivered to the heroine's apartment , and so forth .sx A recent effort , perhaps harmless in intention but unspeakable in execution , has been made to introduce a women's angle into the field , whereby we are introduced to a gallant little lady pretending to hate her man so that he can push off to Mars without pining for her , and an equally gallant little wife and mother uncomplainingly keeping up the production of tasty and nourishing meals while the hydrogen missiles are landing in the back garden .sx We can hope for more imaginative treatments than that , but the role of sex in science fiction as a whole seems bound to remain secondary .sx In the idea type of story it can have almost no place ; in the social utopia , it exceeds its warrant if it is much more than illustrative or diversifying , although one would not want to be decisive at what is still an early stage of the medium's development .sx To view with aplomb the prospect of continuing limitation of sex interest in science fiction is not the same thing as to accept a damaging poverty in it , for we are dealing with a genre , not a literature , and it is unnecessary to chide the Aeneid , for instance , on the grounds of its taciturnity about daily life in Augustan Rome .sx But I quite agree that almost nothing in contemporary science fiction is more calculated to affront the tiro , nor to raise more serious doubts of the medium's ability to come of age , than the horrid lyricism or posturing off-handedness which seem to be the regular procedures for handling these questions .sx Similar doubts attend consideration of another , and I suppose , related , weakness in the medium as at present conducted :sx lack of humour and , far more than this , bad attempted humour .sx There is undoubtedly a kind of priggish pomposity which can afflict even the better writers , enough at times to subvert the moral tendency of what they are saying , and I connect this with the parochial circuit of mutual congratulation , leading in some cases to delusions of grandeur , in which most of them are involved ; this is a consequence , I feel , of the history and general circumstances of science fiction itself .sx As regards simple absence of humour , I like to think I'm as fond of a good laugh as the next man , but I can stand doing without for long periods when reading , having been trained in the Oxford English school , and many of the best science-fiction stories , " The Xi Effect , " for example , distil a kind of horror hard to conceive of as harmonising plausibly with anything comic .sx Some editors in the field , however , seem to have picked up from their reading the notion that humour is a sign of maturity , and compete with one another to fill their pages with stories whose very titles are enough to chill the blood :sx " The Cerebrative Psittacoid , " for instance , or " The Gnurrs Come from the Voodvork Out .sx " There is even a whole mass of writing consecrated to the defeats inflicted on learned but hidebound scientists by a generic Midwestern Paw and Maw of great natural wisdom ( alleged ) and hideous whimsicality ( actual) .sx The British are not guiltless here either :sx a story called " When Grandfather Flew to the Moon " married the concepts of space travel with traditional- that is , false and folksy- Welsh humour , introducing characters called Llewellyn Time Machine and Auntie Spaceship-Repairs Jones .sx This outstanding case of unwanted originality won a prize in the London Observer's science-fiction contest , which seems to have been judged by non-addicts ; it has been reprinted , with squeals of editorial delight , in a leading American anthology .sx However , the picture as a whole is not as grave as this .sx Humour as a main interest will sometimes work in this medium , provided that the comic notion is a valid science-fiction notion as well .sx One such example is William Tenn's satire on mediocrity , " Null-P" ; others are to be found in the work of Sheckley , Pohl , and Fredric Brown .sx Beside his contributions to the comic-inferno division in stories like " A Ticket to Tranai , " Sheckley has devised a sub-form of his own , the comic problem .sx In " The Lifeboat Mutiny , " two men strive to outwit the mechanical intelligence which controls the boat ; it was programmed to meet the needs of an extinct , warlike , reptilian race and is of a verbose , officious disposition .sx Finally the men sham dead and the lifeboat ejects them into the sea , having read the alien burial service over them .sx The comedy here arises from the characterisation of the non-human protagonist as it lectures the men on their patriotic duty , offers them food that looks like clay but smells like machine oil , and when they refuse it , threatens them with brain surgery .sx The solution to the problem , however , does not approach the theorematical neatness and cogency of that propounded in " One Man's Poison .sx " Here , two other but similar men are starving to death in a vast , isolated alien warehouse filled with various outlandish goods , including food , poisonous substances , and a thing called the Super Custom Transport , complete with fuel .sx The food turns out to be poison and so does the poison , whereupon the men settle down to dine off the Super Custom Transport , which proves to be an animal , and its fuel , which is water .sx Better than almost any other , this example of the science fiction of pure idea acts as a test case , in that those learned in the medium will at once salute its ingenuity and elegance , while those whose study is but little will complain of not being illuminated , of being offered an unworthy escape from the universe of man and fact , of being presented with a pseudo-question instead of a question .sx