Rev Richard James asks:

Of your four unsmiling gods of science, how many can prove they exist, how many merely believe it, and how many are in self-denial?

The question of what constitutes proof is a vexed one! Philosophers of science often disagree, and there is no single set of criteria which is universally thought to constitute “proof”.

However, there is extensive audiovisual evidence for the existence of all four scientists (David Attenborough, Brian Cox, Richard Dawkins and Stephen Hawking). In some cases this evidence dates from the 70s and 80s, making it impossible that it could have been computer-generated. Their physical existence has also been widely observed and documented, often by fellow scientists.

This sort of documentary and in-person evidence is generally considered proof of the existence of, for example, a species of bird, but perhaps Richard considers it insufficient in this case. If Attenborough, Cox, Dawkins and Hawking were minded to prove their existence more rigorously, they could certainly devise an experiment to do so. To begin with, perhaps they could prepare two identical rooms, to be monitored by neutral scientifically-trained observers; lock themselves in one room, without telling the observers which; and proceed to have conversations, move objects about, and perhaps write their names on a blackboard. The neutral observers could compare the activity in this room to another, “control” room, and demonstrate the existence at least of a force which converses, moves, and declares itself to be Attenborough, Cox, Dawkins and Hawking. As the four are well-versed in the ways of science, they could use the conversation to come up with further experiments that would make the demonstration conclusive.

By some definitions of proof, it’s considered important not just to carry out an experiment but also to have it published in a peer-reviewed journal. For most scientists, an experiment which merely proves their existence might – since this claim is widely considered uncontentious – be difficult to place. However, considering the stature and fame of Attenborough, Cox, Dawkins and Hawking, it is likely that any study they chose to make would find a home.

Linda Moran asks:

David Attenborough, Brian Cox and John Simm all in one magazine? Christmas is very early this year.

We’re always pleased to see letter-writers answer their own rhetorical questions, but in this case Linda has fallen into error. Christmas hasn’t come early at all – instead, it merely happened that one edition of the Magazine contained so many features of particular interest to Linda that it felt as exciting as a well-considered Christmas gift. It’s an easy mistake to make!

If Linda wants any more evidence, she can merely examine the rest of that week’s magazine, which contains none of the comedic gift guides, Christmas-themed features, festive recipes or holiday-season fashion advice that one would expect in a Christmas edition.

Victoria Moore asks:

I’d like to apologist to supporters of Fulham FC. For my 28 August column, I wrote that “the existence of Fulham keeps people who like to turn up the collar of their T-shirts… out of the rest of London”. I hadn’t mentioned football at all. Someone mysteriously inserted the initials FC. A rogue Guardian Chelsea fan?

It’s more likely that a subeditor assumed Victoria intended to refer to the football club, and “corrected” her while under this misapprehension.

It’s an understandable mistake. Many people are relatively unaware of the existence of Fulham as a suburb, and know the name primarily as belonging to the club. A Google search for “Fulham” returns many prominent references to the sports team, and few to the suburb; 90% of the top ten results, 78% of the top fifty results, and 50% of the top hundred results relate to Fulham FC.

Sheila Hannay asks:

With several big family occasions to mark, could I have Lucy Mangan’s page (11 September)? It would save me buying cards and stamps.

Sadly for Sheila, no. Mangan has been writing for the Guardian since 2003, and they’ve shown no sign of wishing to replace her; but if they did decide to do so, then it’s likely that they’d seek someone who writes significantly differently, rather than someone who seeks to replicate the content of her columns. There would be little point in making the change otherwise.

But Sheila shouldn’t fret – if she were given Mangan’s page, she might find it rather less useful than she hopes! A close examination of the column in question shows that Mangan wrote it after a family gathering to celebrate her parents’ anniversary. This suggests that it was intended to augment, rather than replace, a traditional card.