The title is a bit over dramatic but, per the title, if you could contribute with one piece of knowledge to a book that every single individual should learn from in order to kickstart a civilization, what would be yours?
My personal choice would be the process of soap making, from scratch.
Yet you still fail to contribute friend…let’s see your proposals.
I’ve been informed that I misunderstood the question and we can offer to contribute whatever we would like regardless of our qualifications. If that’s the case, I would propose antibiotics.