@lanodan @Moon I think we just got stuck on some minor misunderstanding. Moon said that all Turing machines are equivalent at computation. You remarked that for memory-constrained programs that is not the case, and the Turing machine does not exist IRL. And to that I argued that there are only finite computers IRL, therefore equivalent to finite-state machines, finite automata, regular expressions…, which are also all equivalent at computation :-)