Equally influential was von Neumann's (1955) discussion of the necessity of an epistemic cut in any measurement process (see Sec. 9) showing that the function of measurement is necessarily irreducible to the dynamics of the measuring device. This logic is closely related to the necessary separation of symbols and dynamics for control of self-replication since measurement and control are inverse processes, i.e., measurement transforms physical states to symbols in memory, while memory-stored controls transform symbols to physical states.
H.Pattee: The Physics of Symbols: Bridging the Epistemic Cut. [Полужирный шрифт мой -- mns2012]