So how have these two concepts translated into a legal context, Jasper?

Well, the law has had to make choices between these models, not always conscious that that's what it's doing.But different courts have come down on different sides of the debate.

So in a US case, the Massachusetts Supreme Court in 1891, looking all the way back to O'Brien and Cunard SS Company, has quite an interesting set of facts.

So a woman joined a line of passengers who were being examined by a surgeon on a boat bound for Boston, and the surgeon was examining each patient, determining whether to administer a smallpox vaccine and then administering the vaccine if indicated.

The claimant was told that she should be vaccinated by the surgeon, and she held out her arm for vaccination.

But she later sued saying that she hadn't consented.

And dismissing her claim, the court held that if the claimant's behavior was such as to indicate consent on her part, the surgeon was justified in his act, whatever her unexpressed feelings may have been.

Jasper, how did this change how we understand consent in a medical context?