The Three Note Corn Trinity

No one thought of it before that, as far as we can tell. That's one of the great mysteries. Is that due to the progress and development of music? Up until about 1000 AD, remember in Western music, people were singing single lines of notes. They weren't singing combined notes. And then they discover that it develops very fast. So there would have been at least 500 years to think about, about those things. But it didn't happen. Now I'm ready to be proved wrong on that. It seems to me, once you've seen that or heard it, it seems so obvious. But for some reason, no one did until about 1500.