This is a linkpost for https://foundational-research.org/s-risks-talk-eag-boston-2017/
They said "adjacent in design space". The Levenshtein distance between return val; and return -val; is 1.
So being served a cup of coffee and being served a cup of pure capsaicin are "adjacent in design space"? Maybe, but funny how that problem doesn't arise or even worry anyone...