Modeling Human Decision-Making: An Overview of the Brussels Quantum Approach

  • Diederik Aerts
  • Massimiliano Sassoli de BianchiEmail author
  • Sandro Sozzo
  • Tomas Veloz


We present the fundamentals of the quantum theoretical approach we have developed in the last decade to model cognitive phenomena that resisted modeling by means of classical logical and probabilistic structures, like Boolean, Kolmogorovian and, more generally, set theoretical structures. We firstly sketch the operational-realistic foundations of conceptual entities, i.e. concepts, conceptual combinations, propositions, decision-making entities, etc. Then, we briefly illustrate the application of the quantum formalism in Hilbert space to represent combinations of natural concepts, discussing its success in modeling a wide range of empirical data on concepts and their conjunction, disjunction and negation. Next, we naturally extend the quantum theoretical approach to model some long-standing ‘fallacies of human reasoning’, namely, the ‘conjunction fallacy’ and the ‘disjunction effect’. Finally, we put forward an explanatory hypothesis according to which human reasoning is a defined superposition of ‘emergent reasoning’ and ‘logical reasoning’, where the former generally prevails over the latter. The quantum theoretical approach explains human fallacies as the consequence of genuine quantum structures in human reasoning, i.e. ‘contextuality’, ‘emergence’, ‘entanglement’, ‘interference’ and ‘superposition’. As such, it is alternative to the Kahneman–Tversky research programme, which instead aims to explain human fallacies in terms of ‘individual heuristics and biases’.


Quantum structures Cognition Concept theory Decision theory Human reasoning 


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Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  • Diederik Aerts
    • 1
  • Massimiliano Sassoli de Bianchi
    • 2
    • 3
    Email author
  • Sandro Sozzo
    • 4
  • Tomas Veloz
    • 5
    • 6
  1. 1.Department of Mathematics, Center Leo Apostel for Interdisciplinary StudiesBrussels Free UniversityBrusselsBelgium
  2. 2.Center Leo Apostel for Interdisciplinary StudiesBrussels Free UniversityBrusselsBelgium
  3. 3.Laboratorio di Autoricerca di BaseBarbengoSwitzerland
  4. 4.School of Business and Centre IQSCSUniversity of LeicesterLeicesterUK
  5. 5.Departamento Ciencias Biológicas, Facultad Ciencias de la VidaUniversidad Andres BelloSantiagoChile
  6. 6.Instituto de Filosofía y Ciencias de la ComplejidadÑuñoaChile

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