Searle doesn't make an argument about formally equivalent Turing machines, he makes an argument about a person using an instruction book to manipulate strange c

Searle doesn't make an argument about formally equivalent Turing machines, he makes an argument about a person using an instruction book to manipulate strange characters. Right, this discussion is imcomplete without bringing in Church's thesis. * So to hold a conversation about the weather, we'll need to add some separate input channels to observe the outside world, and to talk about the Room's plans for today, we'll need to throw in something that can keep track of time, .... it just goes on.* Or these could be predefined and static. (And while you're adding all the extra machinery, don't forget that even the original book is incalculably large, not the merely hefty tome that you're picturing in your mind's eye.) This is like objecting that a Turing machine would take too many steps to solve a sufficiently large instance of some problem (e.g. more than there are Planck times in the age of the universe). The problem is still Turing-computable.