The digital physics everything-is-computation view of the universe is also not obviously wrong; it is taken seriously, as you say. But even if the universe is c

The digital physics everything-is-computation view of the universe is also not obviously wrong; it is taken seriously, as you say. But even if the universe is computational there's presently no example of running a human-defined instruction sequence at that fundamental level. The quote I was reacting to emphasizes feasibility: "To appreciate the feasibility of computing with no energy and no heat, consider the computation that takes place in an ordinary rock." There's precious little to suggest feasible computing with a rock. (Or to suggest other feasible ways to run computations of interest to humans with no input energy and no waste.) It's like reading "to appreciate the feasibility of supplying civilization's electricity sustainably, consider the energy released when two neutron stars collide." Both are strong contenders for "among the least feasible engineering programs not yet proven outright impossible."