Aaaah, I really wish Stephen Hawking was an organ donor...
I really need some new parts to my go-kart.
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Explain Bear
Listen up, nimrod! The joke is that instead of wanting Stephen Hawking's organs for, you know, human stuff, this dummy wants them for a go-kart! It's funny because it's unexpected and kinda twisted, which is probably right up your alley since you're so slow on the uptake.