The very mention of Gulliver and his travels, I have recently discovered, is likely to elicit the strangest reactions. One of my friends has been haunted by the book since childhood, when a pop-up illustration of Gulliver tied down by hundreds of Lilliputian ropes gave her a first frisson of sexual surrender. Another has fond memories of studying Gulliver’s Travels for A-level two decades ago and persuading his teacher that, rather than produce essays analysing Swift’s novel, he and his classmates could collaborate on a poster featuring drawings of furry Yahoos. It’s that kind of book.

Few novels, in fact, have had such power to haunt, enchant and disturb. A gigantic Gulliver putting out the fire in the Lilliputian palace by pissing on it, a miniature Gulliver fending off wasps as large as partridges in Brobdingnag, an abashed Gulliver discovering that in the land of the Houyhnhnms humanity has been reduced to gibbering Yahoos. Rarely has a novel produced so many episodes and scenes that have entered the collective imagination. And rarely has a novel provoked such violently different reactions so much so that Gulliver’s Travels acts as a literary litmus test to the principles, attitudes and fears of its readers.

When the book was first published in 1726, the immediate reaction was one of universal delight. Swift’s great friend Alexander Pope wrote to assure him that the book was read “from the cabinet council to the nursery”. Ten thousand copies were sold within three weeks of publication, and soon pirate editions and translations into French and Dutch had also appeared. The combination of political satire, scatological wit, literary parodies and, above all, the brilliantly simple fables in the storyline confirmed to Swift’s contemporaries that he was, as Addison said, “the greatest genius of the age”.

By the end of the 18th century, however, Swift and Gulliver were hated and reviled, due in no small part to the hostility of Dr Johnson who condemned the book as the sinister product of an author whose vile hatred of humanity drove him to terminal insanity. It was a fine double whammy, with this warped account of author and book providing evidence against each other. Walter Scott followed suit, judging Gulliver’s Travels to be the “severe, unjust and degrading” vision of Swift’s “gloomy misanthropy”.

Scott was charitable by comparison with the Victorians who refused to stomach Swift’s strong meat. Even Edmund Gosse found his customary benevolence tested when he took pity on a mind capable of conjuring up such a “sinister masterpiece”. But it was Thackeray who really let rip. Gulliver’s Travels was “Horrible, shameful, unmanly, blasphemous” and Swift “the most wretched being in God’s world” who “entered the nursery with the tread and gaiety of an ogre”.

Why this level of vilification? Clearly, Swift had not displayed the proper “Victorian values”. On the contrary in the conflict between Lilliput and Blefuscu, for example, he had shown the humbug behind patriotism, he had lampooned glib notions of scientific progress with the creation of the ridiculous inhabitants of Laputa and Lagado, and then, or course, he had ended up reducing mankind to those vile Yahoos.

Just as, or even more, upsetting was the manner in which Swift revelled in his disgust at the human body. Where middle-class Victorians coped with the corporeal by hiding it behind locked doors and layers of clothing, Swift relished describing not only the horror with which Gulliver looked on the pock marks and sores of the great beauties of Brobdingnag but also the problems his hero faced in performing his massive ablutions in Lilliput.

The misreadings of critics such as Thackeray add a real poignancy to the scene in Glubbdubdrib, where Gulliver is entertained by the ghosts of great classical authors, accompanied by the shades of their commentators who are racked by shame and guilt, for they now appreciate how appallingly they misrepresented the work of their subjects.

But Swift and Gulliver have also found their champions, most fervently from political radicals Hazlitt, Leigh Hunt and Cobbett were among their great admirers in the 19th century, and in our own Swift has been vividly appreciated by the likes of George Orwell and Michael Foot.

At first sight, this may seem odd, because Swift was a Tory and convinced reactionary. Nevertheless, he has been cherished by the literary Left because of his unerring ability to expose not just human folly in general but specifically the stupidities and corruption that accompany the follies of power. This leads Orwell partly to pardon Swift as a “Tory anarchist” who was propelled mainly by hatred of the Whigs, but he has to concede that he cannot sympathise with many of his preferences and prejudices, especially in their expression in Swift’s Utopian vision of the Houyhnhnms a species that has no use for science or indeed any form of curiosity, love, or hedonism. This dire Utopia encouraged Michael Foot to continue his rehabilitation of Swift by claiming that he was actually offering another satire here and describing his true ideal in the society of Brobdingnag an interpretation that has the one disadvantage of being completely wrong.

The truth of the matter is that Gulliver’s Travels continues to be an immensely problematic book. Some of the problems facing present-day readers are specific and minor. Much of the political satire which had Swift’s contemporaries guffawing has little or no resonance now whereas, say, the conflict between the Big Endians and the Little Endians (a civil war between factions who disagreed about how to open a boiled egg) has a timeless appeal.

Much of Swift’s invective now seems fairly ham-fisted and often silly, not just when he attacks his own political foes. His satirical dismissal of intellectuals and scientists as a bunch of fools, whose discoveries and pursuit of abstract knowledge are all daft and useless, will only strike chords with the most Luddite of philistines. And then there is his eminently troubling indignation at humankind in general.

The least sympathetic part of the novel, to my mind, is Gulliver’s encounter with the Houyhnhnms. Granted, in a century which has witnessed Hiroshima and the Holocaust, any portrayal of humanity as bestial carries real force. But those Yahoos just don’t convince. Are they humans or not? And if human beings are so ghastly why do the Houyhnhnms have to behave anthropomorphically, sitting down on their flanks, pacing up and down as they have chats and so forth? And if those dull, passionless, smug, backward horses constitute some sort of ideal, then I am six inches tall.

Where contemporary readers enjoy a real advantage over Swift’s Victorian enemies is in being able to enjoy many of his more revolting accounts of the body, especially those describing Gulliver’s troubles in Bobdingnag. To readers accustomed to science documentaries and microscopic photographs which blow up to enormous size the parasites and bacteria inhabiting our bodies, Gulliver’s stunned reaction to the all-too-noticeable defects of the Brobdingnagians will seem only realistic, even if Swift does dwell on this with uncomfortable insistence.

I feel it wise to end on that more positive note, for, as Hazlitt pointed out, the distinguishing feature of Swift’s satire is his ability to “tear off the mask of imposture from the world; and nothing but imposture has a right to complain of it”. In Gulliver’s Travels Swift tore off that mask with such aplomb that, 250 years after his death, his inventions enjoy as vigorous a life as ever the Lilliputians with their hilarious war with Blefuscu, the Brobdingnagian ladies of fashion oblivious to Gulliver’s disgust, the intellectuals of Laputa with their heads so literally in the clouds that their tailor measures them for suits with a quadrant, ruler and compasses.

My own favourites are those academicians of Lagado who aim to extract sunlight from cucumbers, build houses from the top to the bottom, distinguish colours by their smell and regain food from excrement. Lest anyone think scientists could never be so stupid, Swift provides his best punch-line of all every one of these experiments had actually been conducted by venerable members of the Royal Society. Touche.