Oh you are a sick, sick man. Now I know why you rooted for the Aussies so hard during the World Cup.
 

Do you have to know how to swim in order to scuba dive?
 

Um....yes.
 

Practically speaking, perhaps. But hypothetically, is that definitively so? Certainly if swimming is defined as that which you do while staying on the surface and keeping your nose and mouth mostly out of the water, scuba diving would seem possible without knowing how to swim, because the idea is to go under the surface and your nose and mouth are (I believe) covered. True, if you don't know how to swim, you're quite likely to panic when you get in the water and especially when you put your head under. But if you can stop yourself from panicking, I would think you can scuba dive without swimming. You have an inflatable vest to hold you up when needed (its called a BCD I think), and the rest of the time you're under the water, breathing air and basically just floating around, right?