There will be no cherry-picking. We will respect the European ban on that delightful but unrealistically self-indulgent activity. So said Theresa May, in a statement which was clearly intended to show the Europeans, and the Scots Nats, that she can be relied on to negotiate in good faith.

The position on cake is not yet quite so clear. As Jeremy Corbyn observed, in a the course of a reply which was well above his usual standard, the Foreign Secretary thinks we can have our cake and eat it, while the Chancellor says we cannot have our cake and eat it.

Corbyn is right to say that although the language used is “flippant”, the difference in outlook is genuine. The Prime Minister seems to lean towards the Chancellor’s view: not for her the ebullitions of evasive optimism behind which Boris Johnson sometimes conceals his real opinions.

And yet she is, in the end, an optimist. She believes Brexit will work, and knows what is needed to make it work, namely a settlement which works for every part of the United Kingdom.

How platitudinous that statement sounds. But May will stand or fall as a Unionist, and by her frequent heartfelt references yesterday to the UK she confirmed that she knows this.

She can only beat off the challenge from the Scots Nats by demonstrating that life is better and richer within the UK, and preserve peace in Northern Ireland by reaching a settlement with the Republic that works for everyone.

No wonder she resorts even more often than most politicians to a small number of stock phrases, including “a country that works for everyone”. Such safe, inclusive language is meant to reassure everyone that she will be a safe, inclusive negotiator.

As the Duke of Wellington remarked, when the great task at last arrived of making an enduring European peace after the Napoleonic wars: “Be sure that in politics there is nothing stable except that which is in everyone’s interests.”