“Brian: Stephen, your 'motor-mouth' disease, does it affect, um... Stephen Hawking: What? Brian: [Gesturing towards his crotch] Uh, everything? Stephen Hawking: What? No. Different system. Automatic. Brian: Are you serious? Well that's pretty wonderful isn't it? Well it certainly explains a lot about…”
— Anthony McCarten, Stephen Hawking, Eddie Redmayne, imdb.com