Expanded version of the argument: "Karpathy says 'people drive vision-only' and apparently intends that to convince us that vision-only is good enough. But (1) those people driving vision-only are using human brains, whose abilities we have not yet come close to duplicating, and (2) even with the astonishing abilities of the human brain, those people driving vision-only make a lot of mistakes and have a lot of accidents, and we want self-driving cars to be much safer than that. So the fact that people drive vision-only is no reason to think that self-driving cars should do likewise. They're trying to be safer than people, with less computing power; why shouldn't we make up for that by giving them extra sensors?"