Quantum Structure in Cognition

TL;DR

This paper explores how quantum mechanical principles can model complex human cognition and concept combinations, revealing a two-layer structure of thought and explaining various cognitive phenomena through quantum effects.

Contribution

It introduces a quantum modeling framework for concept combinations, demonstrating its ability to explain non-classical effects in cognition that classical models cannot account for.

Findings

Quantum principles explain concept combination effects like overextension.

A two-layer structure of human thought is proposed: classical and quantum layers.

Quantum models account for cognitive phenomena such as the conjunction fallacy.

Abstract

The broader scope of our investigations is the search for the way in which concepts and their combinations carry and influence meaning and what this implies for human thought. More specifically, we examine the use of the mathematical formalism of quantum mechanics as a modeling instrument and propose a general mathematical modeling scheme for the combinations of concepts. We point out that quantum mechanical principles, such as superposition and interference, are at the origin of specific effects in cognition related to concept combinations, such as the guppy effect and the overextension and underextension of membership weights of items. We work out a concrete quantum mechanical model for a large set of experimental data of membership weights with overextension and underextension of items with respect to the conjunction and disjunction of pairs of concepts, and show that no classical model is possible for these data. We put forward an explanation by linking the presence of quantum aspects that model concept combinations to the basic process of concept formation. We investigate the implications of our quantum modeling scheme for the structure of human thought, and show the presence of a two-layer structure consisting of a classical logical layer and a quantum conceptual layer. We consider connections between our findings and phenomena such as the disjunction effect and the conjunction fallacy in decision theory, violations of the sure thing principle, and the Allais and Elsberg paradoxes in economics.