GEB explores a similar idea in investigating where a program is written It's implied that the distinctions are somewhat arbitrary. For example, a song is "writ

GEB explores a similar idea in investigating where a program is written It's implied that the distinctions are somewhat arbitrary. For example, a song is "written" on a record with a bunch of grooves, and the record-player is the machine that plays it. But if the record-player spun backwards instead of forwards, you'd hear something completely different. So in some sense, the record-player also holds part of the program. And all this runs parallel to the idea that a program is also data, IMO. I think a 'non-arbitrary' definition of a machine would be very general.