Is Bitcoin a Proof of Work?

I think you did a great job kind of articulating that transition between different scales of blockchains and I think obviously it's a good segue into your third piece the law of hash universality quite astronomy part three. Proof of work is this shelling point for money and maybe we can kind of move from there into the language side of things, he says. How natural is bitcoin as an invention even for human beings? Is it a very conditional invention or is it a very like inevitable invention in terms of how species discover new technologies such as fusion or computing or semiconductors  or is it something that is conditional and we kind of invented it because of where weird and not every species would