A sadist is honest about his intentions. That probably wasn't funny, but what do I know?
A bird can fly but a fly can't bird.
A radius
Cleaver! EDIT: Also Sharp, knew about this one but I like Cleaver better.
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Hit me.* What did the sadist say to the masochist *No.*
Nothing.
Pedants !
Cessna: "To get my Commercial Pilots Licence and Instrument Rating." ATC: "I meant in the next five minutes not years."
For the same reason dogs chase cars they have no intention of driving...