I had the same thought.
The modern binary systems or western adopted one is from around 1700 and genetics etc. as a subject is quite new.
So he's talking the things as you have been taught or aware of and comparing them to similar binary logic from way back when.
The key really is that prior to the adoption of algebra in the west by scholarly academia the what was zero?
Zero was treated as a something, a real thing. Funny thing is it led to better problem solving.