Perfectly true, and I quite agree that was a weak argument for him to have put up, and it deserve to be put down.

But the distinction I was making is not a weak argument. Smoking in a room does interfere with the enjoyment of other people, and the evidence is that it also threatens their health.

Even if the smokers were in a majority, that applies - and that is the logic behind the Irish Supreme Court decision that resulted in the ban on smoking in Irish pubs, because it centred on the right of the person serving the drinks not to have to breathe other people's smoke smoke in his or her place of work.

The analogy with car fumes is a valid one, and legal restrictions on car emissions already go some way towards meeting it. In time they should go a lot further. However I suspect that there are relatively few closed rooms where you will find an internal combustion engine being operated - and there's probably a law against it already.