It is perhaps the last great question of contemporary philosophy: if David Davis cannot conceive of it, can it be real?

Let’s begin with a purely conceptual example: somebody clever than David Davis. Of course, David Davis himself cannot conceive of such a thing, nor can its existence be empirically proved, but this should not close us off at least to the possibility of its existence.

And now a real one. For David Davis, it is ‘inconceivable’ that parliament will not be given a vote on the final terms of Britain’s exit from the European Union. He said as much to a House of Lords committee just two weeks ago. So the Secretary of State for Exiting the European Union will have found himself plunged into an existential thought experiment of unsettling complexity by our new Prime Minister’s first ever appearance before Parliament’s all high Liaison Committee.

Ms May was asked this very question three times, both by Hilary Benn and by the committee chair Andrew Tyrie, both men generously adding the clarifying suffix: ‘yes or no?’

Only the first of these answers, you will know, falls within the range of Davis’s conceivability, a range considered, by him and perhaps by others, to form the boundary of human knowledge.

So what followed came straight from the realm of science fiction. “We will make sure Parliament has the opportunity to discuss these matters,” the Prime Minister assured.

Mr Tyrie tried again.

“We will not be setting out on an hour by hour basis, a running commentary,” the Prime Minister replied.

“I think people are hearing a ‘no’?” Mr Tyrie suggested, to some laughter.

“I gave the answer I gave,” Ms May insisted, to even more.

This happened only a few hours ago, but that there have been no confirmed public sightings of Mr Davis since must lead us to the sorry conclusion that it is indeed conceivable - likely even - that there will in fact be no parliamentary vote on the terms of Brexit, and that the Brexit Minister’s head has therefore exploded.

Poor David Davis. The once inconceivable made suddenly real. It were as if Job and Ecclesiastes were sharing a quiet pint, opining on the unknowability of God only for the Almighty to walk in, show them his To Do list for the week and ask for ten ones for the fruity.

For the few of us who survived this earth shattering revelation, it was a chance to savour the sweet fruits of an ever more sophisticated political culture. A straightforward question. A non-answer. And then a chance to admire the straight-talking, honest, get-on-with-the-job common sense of our brand new Prime Minister: the simple answer to your question is the rambling obfuscation I have just given you. Don't make me say it all again.