My head hurts. Not through any alcohol-related activities, but because I've been trying to understand where the Government is going with its post-Brexit immigration policy.
Yesterday in China, the Prime Minister ruled out an Australian-style points-based system, the kind which has been advocated by Ukip leader Nigel Farage and, in the run up to the EU Referendum, the now-Foreign Secretary Boris Johnson.
A spokesman for the PM went ever further yesterday, saying that a points system would not form any part of the UK's post-Brexit immigration controls.
In the afternoon, Brexit Secretary David Davis said the reason May had ruled out a points-system was because: "She was concerned that a points-based system was actually too open-ended, that it did not actually put a control on the number of people coming to the UK and therefore she wanted something which sounded like it would more rigorous, not less."
There are two key words here: "sounded like." Is it possible that Davis is guessing at what the Prime Minister wants?
Surely there can be no confusion over such a fundamental aspect of Brexit?
Except of course, there is. Because what May also said in China yesterday was: "What the British people voted for on the 23rd of June was to bring some control into the movement of people from the European Union into the UK."
Two more key words: "Some control". That qualification of "control" is telling.
She went on: "A points-based system does not give you that control."
A strange statement, especially as the Australian High Commissioner to the UK pointed out in Parliament yesterday that a points-based system gives you exactly that.
Under the Aussie system, applicants have to speak English, have to be under 50 years old, and have to pass a health test.
The Australian Government even limits the numbers. Speaking in front of the All-Party Parliamentary Group on Social Integration, High Commissioner, Alexander Downer said: "We decide that we will take, for example, 78,000 skilled migrants and that's how many visas we will issue."
He added: "Even with the family reunion [visas], and like I say that is largely the partners of Australian citizens, we don't take everybody who applies every year in that year because we've reached capacity.
"We don't just institute a cap. We work out how many people we want in a given year and that's how many visas we will issue."
So this system does limit numbers, and does provide control - complete control - over the quantity and type of immigration.
But May doesn't want it. Why? This anecdote was her justification:
"When I was Home Secretary, David Cameron and I went to Heathrow and we talked to Border Force officers there and we said to them: 'What's the most important thing that we can focus on?' and they said: 'Well you need to look at the issue of students, who come here, who appear to have met, the criteria, the don't speak English, they don't know which institution they are going to and they don't know what course it is they are doing and so the system's being abused, but because they met the criteria, they were automatically allowed in.' That's the problem with the points-based system."
No it's not. That's a problem with not enforcing a points-based system. If people were unable to speak English, or were not real students, that is cheating the system and should be stopped. The system itself is not blame.
Another criticism of the Australian-style points-based system is that it the Aussies have an immigration rate which, per head, is twice the level of the UK.
This is a bizarre argument against adopting it. The UK would be able to decide its own immigration level under this system, and just because the Australian's have selected a relatively high number doesn't mean the British Government would have to.
After all, does every country around the world have the same levels of income tax?
For whatever reason, May has decided a points-based system is a non-starter. So what are the alternatives? The UK could have zero-immigration (not even Farage wants that), or simply have a first come first serve basis: the first 100,000 to turn up at the border every year get let in.
Realistically, the Government could introduce a work-permit system, which would mean applicants would need a job before moving to the UK. This is perceived to be a stricter regime than using a points-system.
But would these work permits carry quality as well as quantity controls? Would, for example, one of the requirements of the permit be that the applicant needs to speak English? Or would the companies issuing the permits simply have to demonstrate a need to recruit from overseas to fill the position? If so, then what is to stop the mass import of manual labour from the continent, which currently happens? The criticism leveled against this kind of immigration is that the workers have poor English, meaning they struggle to integrate. Was this not one of the concerns of millions of Leave voters?
Among all of this, let's not forget that Theresa May said "some control" on movement of people. Perhaps the system will be that any EU citizen with a work permit can move to the UK, meaning there will be no specific cap on numbers.
If the policy is confusing, the politics is just as strange. Leave campaigners called for a points-based system, and Leave won the referendum. Any sense this is not being delivered will surely play into the hands of Ukip. Even if Theresa May did not want the Australian system, she could have quite easily announced there would be a "British-style points-based system". This would have enabled her the wiggle-room to come up with her own system and still be able to sell it as "points-based" - even if it is, in fact, a work permit scheme.
Confusing policy, strange politics.
No wonder my head hurts.