Say that here was a complete scientific and naturalistic solution to the problem of consciousness, what might it look like? There are a number of basic forms it could take. The first, on analogy with theories in physics, would be a comprehensive mathematical description of the phenomenon, one perhaps involving new kinds of mathematics. Such a theory might leave the exact nature of the phenomenon unexplained while furnishing accurate predictions both of what would be required of physical structures so that they could instantiate consciousness, and given such a structure what its 'subjective experience' would be. The theory to be complete would need to contain rich enough rules for the transformation between structure and experience, so that that given any consciousness-instatiating-structure we could tell precisely what its experience would be, and given any sufficiently plausible description of an experiential state we would know how to construct a structure which would 'have' that experience in the appropriate context. Under the first alternative all of this would be on paper and be expressed via symbolic relations without regard to the practical realisability of any of the proposed structures. Indeed, such a theory might be able to answer such questions as to the minimal structure required to instantiate a given comprehensiveness and intensity of consciousness, or about what kinds of consciousness are possible, as for example whether there is a clear distinction between simple consciousness and self-consciousness. A second form that such a theory could take might be that it consisted only of structural prescriptions, rules of transformation, and experiential descriptions, as above, but without the underlying mathematical unification. In other words the problem would be 'solved' by the extension of purely empirical research into AI agents, and in which the experiential component was defined by a sort of modified Turing test. An experiential description of the structure's interactive behaviour would prove to be the only satisfactorily concise one available. The third form of such a theory would be like the second, only as applied to our own brains. In this case the emphasis would fall on the rules of transformation, which would be expected to be detailed and comprehensive and verifiable by validated interventions in both directions. If the first alternative is experience physics, and the second is experience mechanics, the third is experience engineering. All three alternatives seem absurd, but it is hard to pin down exactly where.