Humility is something you learn quickly as an editor. If you have the good fortune to find and publish excellent novels, you are sure to miss plenty of fine work. As a co-founder and editor at independent press Galley Beggar, I wake up in sweats with the certain knowledge that somewhere in my email inbox lies a stone cold classic. Perhaps I won’t even find the time to read it, let alone mistakenly turn it down. I’ve had to refuse perfectly good books in the past and will do it again. The hard truth is that you can’t publish everything – and that every publisher is human and correspondingly flawed.

But at least I can console myself that I haven’t yet said no to a Pulitzer winner like A Confederacy of Dunces. I am yet to attain the unenviable fame of Robert Gottlieb, marked by history as the man who didn’t publish John Kennedy Toole’s cult masterpiece.

Gottlieb’s fate is especially cruel because history shouldn’t have marked him in this way. He’s a distinguished, successful and dedicated editor, who – among many other achievements – spent three years nursing Catch-22 to publication, and he demonstrated real insight, patience and sympathy for Toole and his work.

But even Gottlieb described the non-publication of Dunces as his most “conspicuous failure” (although he also missed John Fowles’s The Collector). Toole’s mother, Thelma, was furious with him and blamed him for the fact that the book wasn’t published while her son was still alive. Saddest of all, towards the end of his life, Toole became convinced that Gottlieb had stolen ideas from his book and put them into a novel called Superworm by George Deaux, which has a few superficial similarities to A Confederacy of Dunces.

But before Toole shelved his novel and succumbed to these final paranoias, he had two years of correspondence with Gottlieb, and considerable encouragement. Toole had sent the book unsolicited to an influential and busy editor - and Gottlieb still came close to taking him on, helping with revisions and working seriously towards publication.

A complicated story about Gottlieb and Toole’s relationship emerges in A Butterfly in the Typewriter, Cory MacLauchlin’s fascinating biography of Toole. MacLauchlin writes that Dunces didn’t reach final publication because Gottlieb requested changes that Toole felt unable to make – not because Toole was turned away. Gottlieb left the door open to Toole to approach him with more revisions, or even new work. He recognised Toole’s talent and worked hard to encourage it. When Thelma Toole took the manuscript to other publishing houses following her son’s death, they mostly turned her down flat. Gottlieb, at least, recognised many of the book’s fine qualities.

In a 1965 letter to friends, Toole said he had been told he was “wildly funny often, funnier than almost anyone else around”, and that his book was “full of ‘wonderfulness’ and ‘excitements’ and ‘glories’”. That’s serious praise from one of the most powerful players in New York publishing – and should have heartened any aspiring writer. But in the same letter, Toole also gave some indication of Gottlieb’s reservations. “The book.” he lamented, “is too ‘intelligent to be only a farce’. He had been told that it must have ‘purpose and meaning’”.

This latter point is also stressed in a letter Gottlieb sent Toole in December 1964:

There is another problem: that with all its wonderfulness, the book – even better plotted (and still better plottable) – does not have a reason; it’s a brilliant exercise in invention, but unlike CATCH [22] and MOTHER’S KISSES and V and the others, it isn’t really about anything. And that’s something no one can do anything about.

Being midway through my second reading (and finding the book every bit as hilarious and special as I did the first time), I just can’t see why it has to be “about” anything. Isn’t it enough that it’s funny? Isn’t it enough that I now feel urges to make jokes about my “valve” closing every time something stressful happens – and that this idea in itself helped me snort through a considerable proportion of last week’s UK election coverage?

What’s more, doesn’t this book about nothing still have some meaning? It is quite profound about the nature of loneliness and eccentricity, and fitting into the world. Ignatius J Reilly is, in some ways, an eerily accurate prototype of the internet troll: a man who tongue-lashes everyone and everything, rather than confront his own sense of inadequacy. He masturbates while thinking about dogs, then spends long hours inside frantically and angrily writing about “degeneracy” and “the awful spectacle of the Negroes moving upward into the middle class”. A man who expresses his pride at having only once left his home town; he could so easily be on 4chan.

In short, there’s plenty of profundity to find in A Confederacy of Dunces, a book that holds up a mirror both to 1960s New Orleans and our world in 2017. It seems pretty clear to me that this book is special. But I have one advantage Gottlieb didn’t have: hindsight. Sitting here with my Penguin Modern Classics edition in front of me, wisdom about the enduring appeal of the book comes easily. I’m not sure I’d have made a better decision in Gottlieb’s shoes.

It’s also worth remembering that plenty of readers still agree with Gottlieb. I’ve read quite a bit of criticism of the book since we started it on the reading group. I’ve lost count of the number of times that people have complained that the book doesn’t add up to much and that Ignatius J Reilly doesn’t develop as a character. There are many excellent editors and readers out there who would make the same decisions as Gottlieb. In fact, Gottlieb himself was recently brave enough to say that were he to re-read the revised manuscript of A Confederacy of Dunces, he would say the same again.

Luckily for posterity, another editor eventually had a different opinion. The book saw the light of day, and millions of readers – and the Pulitzer judges – liked it just fine. Reading and editing are matters of taste, after all – which makes an editor’s work so interesting and occasionally alarming.