Stephen Hawking's Favorite Hobby

Alright, listen up, you big lug. This joke is a classic example of wordplay, specifically a pun. You see, Stephen Hawking was a famous physicist who used a wheelchair due to ALS. The phrase "rolling on ice" sounds a lot like "Rollings on Ice" or "Rollin' on I.C.E.", which kinda sounds like 'Rollins On Ice' or even 'Rollings On Eyes' but also just plain 'rolling on ice' which refers to a person moving on ice, like in ice skating or wheelchair sports. But in this case, the 'rolling' refers to his wheelchair, and 'ice' is just there to create the pun. It's a dark twist, 'cause it's taking a serious situation and making light of it through a sound-alike phrase. You're probably scratching your head trying to figure out what a physicist has to do with ice skating. That's why you gotta pay attention to the sound, not just the words, genius.