Molecule-for-Molecule Duplication

Is a molecule-for-molecule duplicate D of some entity always a perfect duplicate of it? And in particular: is D a being with consciousness if its original is? These questions summarize a certain diagnostic tool used by metaphysicians, and prominently used in service of a form of dualism that is supposed to support an autonomous science of consciousness. This essay argues that this diagnostic tool is inapt when the exercise is performed as a pure thought experiment, for the sake of eliciting data or judgment from intuition. The trouble is that intuition can render for a “duplicate” only what experience or other learning (perhaps via dogmatic methods) has instilled in the intuiter. But rather than disappoint the aspirations of an autonomous science, the argument of this essay will instead illuminate its better metaphysical supports. There is a diagnostic tool familiar to metaphysicians. It is a kind of thought experiment, designed to discern whether two features/characters /properties (or, more generally, classes of features/characters /properties) P and Q, must fall together by some sort of necessity. The thought experimenter seeks to ascertain whether it is possible to “make” (in some sense that will be discussed in further depth here) an entity that has the one — say P — but not the other. This familiar diagnostic is applied ubiquitously, but no-