Four Labour MPs walk into a room. Five policies on Brexit emerge.
It's an old joke, but that's how it seems looking at the official opposition right now.
Jeremy Corbyn doesn't want the UK to remain a member of the Single Market, but John McDonnell does.
Chuka Umunna is part of a group determined to hold Brexit campaigners to account for their referendum promises, but it's not clear if they actually agree with those policies, or whether they are just acting out of sheer bloody mindedness.
Owen Smith wants a second referendum, while David Lammy believes Parliament should veto Brexit and stop the madness.
As in 1975, the party most divided by a referendum on Europe is Labour, not the Tories.
So where should Labour go from here?
Analysis of the referendum results by Chris Hanretty of the University of East Anglia suggests that 70% of Labour-held constituencies either probably or definitely voted Leave. Seeing as Labour's official position in the referendum was for Remain, this shows a huge disconnect with the views of the people the party claims to represent.
On that basis, Owen Smith's call for a second referendum seems particularly strange. More than one Labour MP has told me they believe it to be a strategic error, as instead of appealing to the '48%' of Remainers, it comes across as telling the '52%' it got the wrong answer.
In the same vein, some Labour MPs are hoping David Lammy will stop calling for Parliament to vote down Brexit. The vote has happened, and no one likes bad losers.
So with the second referendum/blocking Brexit proposals proving unpopular with MPs, what about the other options?
Chuka Ummuna is chairman of Vote Leave Watch (VLW), an organisation which is planning to scrutinise the claims made by Vote Leave in the run up to referendum as it tried to persuade Brits to back Brexit. But what exactly does it want? Is it calling for all of Vote Leave's policies to be adopted by the Government, even though those involved with VLW campaigned strongly against them in the referendum?
Or does it want merely to flag up which policies aren't being implemented - which presumably it would be pleased about anyway.
Tonight's BBC Question Time laid the tensions in the Labour movement bare, with one audience member winning a round of applause for echoing Theresa May's line that "Brexit means Brexit". On stage, Owen Smith tried to argue that no one knows what the mean - but he could well be missing the point. Instead of trying to guess what May and the Tories mean by Brexit, he should be trying to deduce what Labour voters think Brexit is.
If only there was someone he could ask.
There is, of course. Quite a few people actually, but the two that seem most obvious are Gisela Stuart and Kate Hoey. Both played prominent roles in the EU referendum, with Stuart one of the frontpeople of the official Vote Leave campaigns.
Why haven't these two Labour MPs - who clearly have the pulse of millions of voters - being called into the tent to get their views on how Labour misjudged its supporters? Why aren't they being asked about the kind of immigration system Labour voters want? Why aren't they being asked what they were hearing in the rallies and on the doorsteps?
Perhaps if a couple of those four Labour MPs walking into a room were out and proud Brexiters, the party might be able to come up with one policy, not five.