And there were no fundamental material limitations, like there's not some very rare material that we don't have enough of. We actually have enough with raw materials to take all of human civilization, make it fully sustainable and dramatically increased its trust usage would still be fully sustainable.

One way to think of the progress of a civilization, this may sound a little esoteric, but is percentage completion of scale. So, [Inaudible] scale, one would be you're using all the power of a planet. We're currently less than 1% on Level 1. Level 2 would be using all the power of the sun, and Level 3, all of power of the galaxy, so we've got a long way to go, long way to go.