Going for Level 4 autonomy—where the car drives itself and you can go to sleep—is typically justified on the grounds that such cars will be very safe. And they had better be, or we’d never let them loose on the roads.
But the safety-first argument is flawed, says Gill Pratt, who heads up self-driving car research for Toyota. Reason: Safety can be obtained by other means.
“The reason for Level 4 being done—to save lives—is backwards thinking, even if you assume it’ll be 10 times safer,” he tells IEEE Spectrum. “That’s not the only way to save lives; there are multiple ways to do it.”
Pratt allows that there’s a purely economic argument for self-driving cars—remove the driver and you cut expenses in any commercial application, like taxi service and trucking. But that decides things only after self-driving tech can be proven far better than the best human driver. A system that’s just 10 percent better will win over statisticians and philosophers but not the general public.