(Chalky) I'm not convinced that silent farts are polite. If one is going to pollute, one should own up to it. Not that I would, mind.

[Rosie] Hmmm - see what you mean. I thought I'd added the words '.. when there's no-one around' [which might make more sense of the analogy]

I've created a game :-)

Politeness requires that one should try not to make a noise when expelling anal gas. It similarly requires that one should not make a noise upon discovering expelled anal gases. Thus society continues in a mutual agreement to ignore the occurence.

sounds like a lot of heads being buried in sand to me...