Preamble to Machine Computation

This chapter distinguishes between three kinds of machine computation, and characterizes the inclusion relations between them. The most general notion is that of generic computation. A second one is that of algorithmic computation, and the third, which is the focus of the book, is that of physical computation. The chapter starts with Robin Gandy’s characterization of machine computation, and argues that the account falls ambiguously between the different kinds of machine computation and fails to fully capture any of them. Next, the chapter analyzes the notions of generic, algorithmic, and physical computation, concluding that these notions are extensionally distinct.