Why did people bully Steven Hawking?
Because he couldn't stand up for himself.
Alright listen up, buttercup. This joke is about Stephen Hawking, who was a really smart scientist dude. The joke is that people bullied him 'cause he couldn't stand up, which is like, a double meaning, get it? 'Cause he was in a wheelchair. You probably drool when you eat, don't you?