 Rapaport (2018) provides a more explicit characterization of a computational system defined as any “physical plausible implementation of anything logically equivalent to a universal Turing machine”. Strictly speaking personal computers are not physical Turing machines, but register machines are known to be Turing equivalent. To qualify as computational, systems must be plausible implementations thereof, in that Turing machines, contrary to physical machines, have access to infinite memory space and are, as abstract machines, error free. According to Rapaport’s (2018) definition, any physical implementation of this sort is thus a computational system, including natural systems. This raises the question about which class of natural systems is able to implement Turing equivalent computations. Searle famously argued that anything can be an implementation of a Turing machine, or of a logical equivalent model (Searle 1990). His argument levers on the fact that being a Turing machine is a syntactic property, in that it is all about manipulating tokens of 0’s and 1’s. According to Searle, syntactic properties are not intrinsic to physical systems, but they are assigned to them by an observer. In other words, a physical state of a system is not intrinsically a computational state: there must be an observer, or user, who assigns to that state a computational role. It follows that any system whose behavior can be described as syntactic manipulation of 0’s and 1’s is a computational system.