How Concepts Combine: A Quantum Theoretic Modeling of Human Thought

Models of concepts making use of the mathematical formalisms of quantum theory have been much more successful than other approaches at modeling data generated in studies of concept combination. We show that this is due to quantum modeling considering concepts as entities in states, that change under the influence of context, as compared to a classical fuzzy set view of concepts built from instantiations and features. Furthermore, the quantum approach introduces complex amplitudes giving rise to interference in the statistics of measurement outcomes, while in the classical view statistics of outcomes originates in classical probability weights, without the possibility of interference. The relevance of complex numbers, the appearance of entanglement, and the role of Fock space in explaining contextual emergence, all as unique features of the quantum modeling, are explicitly revealed in this paper by analyzing combinations of concepts.