Bossa Nova raises existential questions.

Bossa Nova couldn't have appeared in Japan in 1530 or England in 1150 or India in 1890. Like the origin of biological species, it hatched from a specific, unintentional series of small steps and variations and collisions over time. Take two families of ordinary squirrels from your local park. Plunk one family on an island in northeastern Canada, plunk a second family on an island in Indonesian, and check back in forty million years.

(I'll wait.)

You now have a plentitude of non-squirrels, dozens of species so different from each other they will be unrecognizable as cousins. Had you not introduced those squirrel families to new homes forty million years earlier, then you would have non-non-squirrels: non-squirrels that could, but don't, exist.

Science and technology have a theory of multiple discovery, which observes that some inventions occur independently in multiple parts of the world around the same time. Some ideas are just ready to emerge once a certain set of memetic conditions are met.

In music, as in biology, this dynamic does not occur.

All this leads to a disquieting consequence: Bossa Nova - or Guangdong music or Indian classical or American Hip Hop - could have easily missed their entrance onto the world stage and never existed. We would lose not only specific albums, but entires mode of organizing sound.

What disturbs me are all the non-non-squirrels out there: genres of music that could have existed, but didn't, and never will. All the unplayed melodies, all the undanced steps, all the unfelt ecstasy.