I realise that the thread is - Mathematics: stupid and clever questions for people who understand.

I do not understand a lot of this as I'm firmly a member of 'The Thickie Mcthickthicks of this world'. However I am enjoying the discussions and some of it does make sense, even to a dimwit like me. If anyone can spare a minute can they explain this 'ridiculously simple' problem to me please.

If 'infinity' is a number and 1, 3, 5, 7, is half an infinity because half of the numbers are missing and I imagine it would be expressed as 'infinity' divided by 2.

But surely 'infinity' is still the same number, and in the sequence above it will always be a half of 'infinity' no matter how far the infinite number sequence progresses, so it can't be different.

I am not expecting a reply. I'm sure you can all solve this in your sleep!