We are barbarians occupying a city built by an advanced civilization, marveling at the hot baths but know nothing about how their builders keep them running. One day, the baths will drain and anyone who remembers how to fill them up will have died.
So long as you live in a city you are probably forgetting most of the ways to survive. I could not even try to discover which berries are edible without killing myself. However, I can teach advanced maths to a largish group of students without much trouble.
Eat a small amount and see if you get sick? Science in the wild...