It's so sad that Stephen Hawking can't stand up for himself.
Stephen Hawking's immobility
Explanation
Explain Bear
Listen up, buttercup! The joke is that Stephen Hawking had a disease that made him unable to stand. Get it? It's funny 'cause it's true, and you probably can't even spell 'Hawking' without Google, you dummy!
Anonymous
He got caught shoplifting. Didn't have a leg to stand on.