AI, Quantum Information, and External Semantic Realism: Searle's Observer-Relativity and Chinese Room, Revisited

In philosophy of mind, Searle contrived two arguments on the impossibility of AI: the Chinese room argument and the one based upon the observer-relativity of computation. The aim of the present article is two-fold: on the one hand, I aim at elucidating implications of the observer-relativity argument to (ontic) pancomputationalism, in particular the quantum informational view of the universe as advocated by Deutsch and Lloyd; on the other, I aim at shedding new light on the Chinese room argument and the nature of linguistic understanding in view of the semantic realism debate in philosophy of logic and language, especially Dummett’s verificationist theory of meaning. In doing so, philosophy of mind turns out to be tightly intertwined with philosophy of logic and language: intelligence is presumably the capacity to reason, and in view of a distinction between statistical and symbolic AI (“AI of sensibility” and “AI of understanding” in Kantian terms), philosophy of logic and language is arguably the part of philosophy of mind that concerns the symbolic realm of intelligence (i.e., the realm of understanding rather than sensibility). More specifically, in the first part of the article, I argue that pancomputationalism cannot be maintained under Searle’s external realism; nevertheless, a radical (external) antirealist position, such as Wheeler’s (“It from Bit”), may allow for a possibility of pancomputationalism. The Searle’s argument and the infinite regress paradox of simulating the universe yield challenges to pancomputationalism and the quantum informational view of the universe, leading us to the concept of weak and strong information physics (just like weak and strong AI). In the second part, I argue that Dummett’s principle of manifestation on linguistic understanding commits Searle to semantic realism due to the nature of his Chinese room argument. Searle’s position must thus be realism in two senses, that is, it has to be external semantic realism. I finally focus upon recent developments of categorical quantum mechanics, and discuss a quantum version of the Chinese room argument. Underpinning all this is the conceptual view that the duality of meaning manifests in different philosophies of logic, language, and mind.