A bit of maths

They say that maths and science etc are best learnt in the morning while the non-science/ artsy stuff are better absorbed later in the day. True enough, I'm inspired this very morning by:

Source: Email from Kel - ask him!

Nothing new, I've said this kind of rubbish before but now that this um, study defines the groups who can suffer this blindness, it sort of revives the mathematician in me..

Let
A = {people who orgasm frequently}
= B U C,
where
B = {women who use vibrators to excess} U {men who masturbate frequently}
C = {women who masturbate otherwise} U {men and women who have sex frequently (and not necessary with each other, just to be inclusive)}

It can thus be inferred that if you belong to set C, you're safe :p