Mitchell: "If something has "the structure of addition", that means it can consistently be interpreted as implementing addition, not that it inherently does so."

Hmm. If a machine can be consistently interpreted as "doing addition", doesn't that indicate that there are intrinsic facts about the machine that have something to do with addition?

Lukas, I don't understand your objection at all. How does disrupting the physical adding machine mid-process prove that it isn't doing addition? One can also disrupt electronic computers mid-process...