Read the peerless Howard Jacobson's speech about Jeremy Corbyn and antisemitism

Mind you, he knows a man who does.  In fact he knows a surprising number of men who do. That he denies ever having been in their company - until photographs turn up of him rubbing noses with them at the gravesides of mass murderers, offering to show them his belief systems if they'll show him theirs - 'Gosh, they're the same size!' - should come as no surprise. You can't spend your whole life in the company of blood-libellers and holocaust-deniers and expect to remember them all by name.

If I may quote from Oscar Wilde's missing play The Self-Importance of Being Jeremy - 'To associate with one antisemite you don't know to be antisemitic, Mr Corbyn, may be regarded as a misfortune, to associate with antisemites on a regular basis looks like a predilection.'

Look - when I think of the scoundrels I've hung around with, I know how easy it is to get people wrong, even when they turn up to meet you wearing hoods and holding burning crosses.  And Jeremy - is it OK if I call him Jeremy? - has never exactly been what you'd call observant.

Take that mural he championed, showing bankers playing Monopoly on the naked backs of the world's oppressed.  You and I, ladies and gentlemen, would look at those greedy, grasping, hooked-nosed, syphilitic, Zionistic financiers and recognize them at once as straight out of the Julius Streicher I-SPY BOOK OF JEWS.  But so innocent of antisemitic caricature is Jeremy, that he didn't see anything remotely offensive. "I didn't look closely," he explained later. How many times does he have to say it, for God's sake! I might have been there but I don't think I was involved.  I don't remember... I didn't look closely....

 If this reminds you of those who lived downwind of the chimneys of Bergen Belsen claiming never to have smelt anything out of the ordinary, I say you have suspicious natures. Corbyn is a busy man. Busy men must take emotional shortcuts. There's an image of a bloodsucking Jew. It's identical to the image of the bloodsucking Jew I already carry in my head. Snap!

 Could there, I wonder, be such a thing as an inadvertent antisemite? Jeremy claims to be a peace-maker. A peace-maker brings warring parties together. Why then do we only ever see him taking Palestinians to tea?  Could it be that he just can't remember to ask the Israelis? "Oh, bugger, I've forgotten to invite the Jews again."

Unless - perish the thought - it isn't peace he wants after all, but the triumph of those he calls comrades and the destruction of those he doesn't.

 According to his supporters, Jeremy Corbyn doesn't have a racist bone in his body.  Just a question, but what is racist bone and how do you know whether another person has one? There are 64 bones in the human arm alone.  Can one be absolutely certain that Jeremy doesn't feel even the tiniest twinge of bone ache, somewhere between the scapula and the humerus, when he sees an alien figure such as I am, coming towards him on Islington Green, carrying the collected speeches of Benjamin Disraeli and humming My Yiddishe Mama?

 And what are we to make - speaking of Corbyn's unconscious - of his inability ever to disavow antisemitism without reminding us of his lifelong opposition to all forms of racism? Which is like answering the question  'Are you a wife-beater?' with an assurance that you always buy The Big Issue.

Because antisemitism isn't quite a racism. It's closer to a superstition: embedded in theology, shrouded in medieval irrationality, updated to suit leftist economics, and exhumed whenever a single explanation for all the evils of the world is sought.  To talk of antisemitism as a racism is a contradiction in terms for Jeremy Corbyn, since in his eyes Jews are neither downtrodden nor exploited but are - as usurers, colonialists and conspirators - the very source and fount of racism themselves. Once hold Jews to be racist, and Zionism a racist endeavour, then no antisemite can ever be a racist himself. And any definition that says otherwise must be amended. 

That's the psychology: now the science. Corbyn's political life has been determined by Newton's First Law of Inertia which states that an object at rest will stay at rest, forever, as long as nothing pushes or pulls on it. In physics the something that might push or pull at it is another object in motion; in socialist politics it is a view contradictory to your own. Corbyn averts his face whenever he hears the word Jew, and rolls his eyes whenever he is asked a question, because he fears the chaos, otherwise known as a change of mind, that might ensue from accepting there's another way of looking at the world.

I will spend my remaining seconds - I don't mean in life, I mean of this speech - telling you why it matters to everyone, not just Jews, that a man so spiteful, sanctimonious and obdurate should never be allowed to do to the country what he's been doing to his party. 

Those who revere Corbyn see it as a virtue that he has never changed his views. Mr Chairman, it is only a virtue to stay faithful to one's views if those views are worth staying faithful to.

To persist in a small erroneousness is the mark of a fool. To persist in a great erroneousness is the mark of a dangerous fool. The ideology in which Corbyn has been pickled for half a century was outworn by the time it reached him. It oversaw the death of millions.  That the ideologies he opposes have scarcely done any better is not an argument for his. You don't have to love the West to refuse the embraces of those whose sole ambition is to blow the West apart ... especially if you want to call yourself a pacifist.

This should have been a golden summer for Labour.  The nightmare that is Brexit, the hell that is Jacob Rees-Mogg, the out-of-season pantomime that is Boris Johnson - from all these Labour ought to have delivered us. But Corbyn did as much as anyone to make Brexit happen with his feeble non-support for Remaining - "I'm seven, erm, seven-and-a-half per cent in favour."

That was one to get us to the barricades. The wrong man - ladies and gentlemen - the wrong man at the wrong time espousing the wrong causes.

I am nothing if not fair: people who are limited in everything but the pleasure they take in themselves are ten a penny in all political parties; they haunt the peripheries, like ghosts-of-the-Christmases-they-don't-believe-in-past, backing losing causes, throwing tea parties for murderers, and looking saintly. Mr Corbyn's misfortune was to be lifted from those peripheries, and dumped haplessly in the centre. 

Not just for our sake but for his, will someone please have pity and dump him back.

Howard Jacobson delivered this on September 6 in favour of the Motion - "Jeremy Corbyn is Unfit to be Prime Minister" - at a debate organised by Intelligence Squared.