Not to mention our attention spans. As the head of Google's self-driving car program told Road & Track, "It's the conundrum of this technology: the better you make it, the more relaxed the human agent behind the wheel becomes. And the more relaxed you become, the less attentive you are."
Case in point, the Tesla autopilot is a driver aid, albeit an advanced one. Drivers don't understand that -- they switch it on and cool their heels, fall asleep, or worse, crash. When you take mental shortcuts and give up crucial components of your decision-making ability, you shift the psychological responsibility to the car itself... but the legal and physical consequences haven't shifted in the slightest.