Knowledge Tree
Roger Penrose
Also known as: Penrose
Facts (75)
Sources
Quantum Approaches to Consciousness plato.stanford.edu Nov 30, 2004 16 facts
claimRoger Penrose proposes that a valid formulation of quantum state reduction must describe an objective physical process he terms 'objective reduction', which is not currently contained within present-day quantum theory.
claimThe proposal by Roger Penrose and Stuart Hameroff is highly speculative, extends beyond the domain of present-day quantum theory, and lacks a clear path for formal development or empirical testing.
claimStuart Hameroff's proposal uses tubulins in microtubuli as the substrate to embed Roger Penrose's theoretical framework neurophysiologically.
referenceRoger Penrose proposed relating elementary conscious acts to gravitation-induced reductions of quantum states, a theory that requires a future framework of quantum gravity.
claimThe quantum consciousness proposal by Roger Penrose and Stuart Hameroff has received outspoken philosophical rejection from critics such as Rick Grush and Patricia Churchland.
referenceHameroff, S.R. and Penrose, R. published the paper 'Conscious events as orchestrated spacetime selections' in the Journal of Consciousness Studies in 1996.
claimRoger Penrose and Stuart Hameroff have argued that microtubuli are the biological structures where gravitation-induced quantum state reductions related to consciousness might occur.
referenceRoger Penrose (1994) sketches ideas regarding non-computable features of quantum gravity in sections 7.8 and 7.10 of his work.
referenceGrush and Churchland (1995) critique Roger Penrose's work in their paper 'Gaps in Penrose's toilings'.
claimRoger Penrose's hypothesis regarding non-algorithmic conscious acts is influenced by his views on creativity, mathematical insight, Gödel's incompleteness theorem, and the existence of a Platonic reality beyond mind and matter.
referenceRoger Penrose authored 'Shadows of the Mind', published by Oxford University Press in 1994.
claimRoger Penrose proposes gravitation-induced objective state reduction by incorporating novel features into quantum theory rather than modifying general relativity.
claimRoger Penrose argues that elementary conscious acts are non-algorithmic, meaning they cannot be described or computed by an algorithm.
claimRoger Penrose and Stuart Hameroff argue that elementary acts of consciousness are non-algorithmic (non-computable) and are neurophysiologically realized as gravitation-induced reductions of coherent superposition states in microtubuli.
claimRoger Penrose's theory of consciousness relies on future developments in quantum gravity to explain the physical process of quantum state reduction, rather than relying on current quantum theory.
claimRoger Penrose suggests that gravitational effects are ideal candidates for playing a role in quantum state reduction because gravitation is the only fundamental interaction not yet integrated into quantum theory.
Quantum Approaches to Consciousness plato.stanford.edu Nov 30, 2004 13 facts
claimThe results from Bandyopadhyay’s lab regarding microtubules initiated significant attention and commentary, as noted by Hameroff and Penrose in 2014.
claimRoger Penrose's conceptual starting point, developed in his books published in 1989 and 1994, is that elementary conscious acts cannot be described algorithmically and therefore cannot be computed. This view is influenced by his background in the nature of creativity, mathematical insight, Gödel’s incompleteness theorems, and the idea of a Platonic reality beyond mind and matter.
claimRick Grush and Patricia Smith Churchland published a critique titled 'Gaps in Penrose’s toilings' in the Journal of Consciousness Studies in 1995, which was subsequently responded to by Roger Penrose and Stuart Hameroff in the same journal.
claimRoger Penrose, in his 1994 work, sketches ideas concerning non-computable features of quantum gravity as potential candidates for explaining gravitation-induced state reduction.
claimRoger Penrose's proposed gravitation-induced objective state reduction is non-computable, distinguishing it from standard stochastic or probabilistic processes which are computable and can be implemented on a computer.
claimStuart Hameroff, an anaesthesiologist, collaborated with Roger Penrose to suggest that microtubules are the location where quantum state reductions can effectively occur.
claimRoger Penrose's theory relating conscious acts to gravitation-induced reductions of quantum states requires a future theory of quantum gravity that has not yet been developed.
claimRoger Penrose and Stuart Hameroff hypothesize that the gravitation-induced collapse of coherent tubulin states corresponds to elementary acts of consciousness.
claimRoger Penrose and Stuart Hameroff developed a scenario claiming that quantum theory is effective for consciousness, specifically arguing that elementary acts of consciousness are non-algorithmic and neurophysiologically realized as gravitation-induced reductions of coherent superposition states in microtubuli.
perspectiveGrush and Churchland (1995) expressed rejection of the quantum consciousness scenario proposed by Penrose and Hameroff, which led to a reply by Penrose and Hameroff in 1995.
claimRoger Penrose and Stuart Hameroff have argued that microtubuli are the potential location for quantum state reductions in the brain.
perspectivePitkänen (2014) argued that the results from Bandyopadhyay’s lab are insufficient to fully confirm the quantum consciousness approach proposed by Hameroff and Penrose.
perspectiveRoger Penrose assumes that a full-blown theory of quantum gravity is required to ultimately understand quantum measurement.
Quantum Approaches to Consciousness plato.stanford.edu Nov 30, 2004 6 facts
claimA consistent framework for the interplay of mental and physical domains of reality using Roger Penrose's mathematical Platonism has not yet been established.
claimRoger Penrose and Stuart Hameroff propose that conscious acts are non-computable, shifting the focus from mental causation to the non-computability of consciousness.
claimRoger Penrose and Stuart Hameroff proposed that microtubules function as quantum computing devices within the brain.
perspectiveRoger Penrose argues that a full-blown theory of quantum gravity is required to understand quantum measurement and the physical process underlying quantum state reduction.
claimThe quantum consciousness proposal by Roger Penrose and Stuart Hameroff extends beyond present-day quantum theory and has initiated empirical research into the function of anesthetics and the operation of microtubules.
perspectiveRoger Penrose proposes that novel features must be incorporated into quantum theory to integrate gravitation, rather than modifying the existing theory of general relativity.
Quantum Theory of Consciousness - Scirp.org. scirp.org 5 facts
claimRoger Penrose and Stuart Hameroff propose that the self-collapse or 'objective reduction' of quantum superposition states serves as the non-computable source for consciousness.
referenceStuart Hameroff and Roger Penrose published 'Consciousness in the Universe: A Review of the “Orch OR” Theory' in Physics of Life Reviews in 2014, which reviews their Orchestrated Objective Reduction theory of consciousness.
referenceStuart Hameroff and Roger Penrose proposed the 'Orch OR' (Orchestrated Objective Reduction) model of consciousness in their 1996 paper 'Conscious Events as Orchestrated Space-Time Selections', published in the Journal of Consciousness Studies.
referenceRoger Penrose, Abner Shimony, Nancy Cartwright, and Stephen Hawking authored 'The Large, the Small and the Human Mind', published by Cambridge University Press in 2000, which discusses the intersection of physics and the human mind.
claimRoger Penrose contends that quantum state collapse occurs naturally due to an objective threshold in the fine-scale structure of the universe, producing the rudiments of phenomenal conscious experience.
Consciousness in Artificial Intelligence? A Framework for Classifying ... arxiv.org Nov 20, 2025 4 facts
claimRoger Penrose and Stuart Hameroff proposed that microtubules in neurons may serve as the site of a quantum-neural nexus, enabling forms of quantum computation.
claimSome researchers, such as Chalmers and McQueen (2022), explore the hypothesis that consciousness is a necessary condition for wave function collapse, which is the converse of the view held by Roger Penrose.
claimRoger Penrose suggests that consciousness might be explainable through the contribution of wave function collapse to the generation of consciousness, implying that consciousness transcends computability.
claimJohn Lucas and Roger Penrose argue that human intellect encompasses truths that no formal or computational system can derive, a position they support by drawing on Gödel’s Second Incompleteness Theorem.
Moving Forward on the Problem of Consciousness - David Chalmers consc.net 4 facts
claimThe psychophysical theory proposed by Stuart Hameroff and Roger Penrose suggests a kinship with Alfred North Whitehead's metaphysics and fits within the Russellian framework.
claimStuart Hameroff and Roger Penrose propose a psychophysical theory where quantum-mechanical reductions of the wave function, occurring at a specific gravitational threshold, are associated with simple events of experience.
accountThe symposium on David Chalmers' paper 'Facing Up to the Problem of Consciousness' included 26 commentaries from various scholars, including Bernard Baars, Douglas Bilodeau, Patricia Churchland, Tom Clark, C.J.S. Clarke, Francis Crick, Christof Koch, Daniel Dennett, Stuart Hameroff, Roger Penrose, Valerie Hardcastle, David Hodgson, Piet Hut, Roger Shepard, Benjamin Libet, E.J. Lowe, Bruce MacLennan, Colin McGinn, Eugene Mills, Kieron O'Hara, Tom Scutt, Mark Price, William Robinson, Gregg Rosenberg, William Seager, Jonathan Shear, Henry Stapp, Francisco Varela, Max Velmans, and Richard Warner.
claimDavid Chalmers notes that Stuart Hameroff and Roger Penrose's work clarifies that they view consciousness as fundamental, rather than explaining it wholly in terms of quantum action in microtubules.
Panpsychism (Stanford Encyclopedia of Philosophy/Fall 2015 Edition) plato.stanford.edu May 23, 2001 3 facts
claimStuart Hameroff and Roger Penrose conjectured that certain systems capable of resisting decoherence are the physical foundation of more complex states of consciousness.
referenceRoger Penrose argued for a non-computational theory of consciousness in his 1989 book 'The Emperor's New Mind'.
claimRoger Penrose (1989), John Searle (1991), Thomas Nagel (1979, 1986, 1999), and Noam Chomsky (1999) have all endorsed, suggested, or hinted at the idea that the problem of consciousness may necessitate a revolutionary change in physics.
Quantum Mechanics And Consciousness: The Physics Of Mind quantumzeitgeist.com Apr 17, 2025 3 facts
claimThe Orchestrated Objective Reduction (Orch-OR) model, proposed by Roger Penrose and Stuart Hameroff, posits that quantum processes within the brain could provide a physical basis for subjective experience.
claimThe Orchestrated Objective Reduction (Orch-OR) theory, proposed by Roger Penrose and Stuart Hameroff, suggests that consciousness arises from quantum computations occurring in microtubules within neurons.
claimRoger Penrose and Stuart Hameroff proposed the Orchestrated Objective Reduction (Orch OR) hypothesis, which posits that microtubules in brain neurons maintain quantum states that affect consciousness.
Six Theories of Consciousness - Mind Matters mindmatters.ai Mar 2, 2026 3 facts
referenceIn his 1989 book The Emperor’s New Mind, Roger Penrose argued that artificial intelligence cannot achieve genuine creativity because computers merely execute algorithms, whereas human creativity and understanding involve non-algorithmic processes.
claimRoger Penrose and Stuart Hameroff proposed that tiny structures in brain cells called microtubules could support quantum effects that contribute to human awareness.
claimRoger Penrose proposed that wavefunction collapse in quantum mechanics could provide the non-algorithmic element necessary for human consciousness.
Panpsychism - Wikipedia en.wikipedia.org 3 facts
perspectiveIn 2017, Roger Penrose rejected criticisms of quantum consciousness theories, arguing that the disagreements are fundamentally about the nature of quantum mechanics.
claimDavid Chalmers believes his variety of panpsychist property dualism, outlined in his 1996 book 'The Conscious Mind', may be the theory Roger Penrose is seeking to reconcile the many-worlds view with observation.
perspectiveRoger Penrose argues that consciousness does not compute, as discussed in a 2017 Nautilus article.
Consciousness-Induced Quantum State Reduction - Nova Spivack novaspivack.com Jun 2, 2025 2 facts
referenceStuart Hameroff and Roger Penrose published 'Consciousness in the universe: A review of the Orch OR theory' in Physics of Life Reviews, 11(1), 39–78, in 2014, which reviews the Orchestrated Objective Reduction (Orch OR) theory of consciousness.
claimPenrose (1989) and Hameroff & Penrose (2014) proposed biophysical models linking consciousness to objective collapse mechanisms involving microtubules, though Tegmark (2000) challenged these models regarding biological feasibility and experimental verification.
Consciousness (Stanford Encyclopedia of Philosophy/Fall 2025 ... plato.stanford.edu Jun 18, 2004 2 facts
claimPhysicist Roger Penrose (1989, 1994) and anesthesiologist Stuart Hameroff (1998) proposed a model of consciousness where consciousness arises through quantum effects occurring within microtubules, which are subcellular structures internal to neurons.
claimScientific and philosophical research into the nature and basis of consciousness experienced a major resurgence in the 1980s and 1990s, involving researchers such as Bernard Baars (1988), Daniel Dennett (1991), Roger Penrose (1989, 1994), Francis Crick (1994), William Lycan (1987, 1996), and David Chalmers (1996).
Quantum mechanics and the puzzle of human consciousness alleninstitute.org May 30, 2024 2 facts
claimRoger Penrose and anesthesiologist Stuart Hameroff hypothesize that microtubules, which are small structures found in neurons and other cells, weave moments of 'proto-consciousness' together to form full consciousness.
claimRoger Penrose, a Nobel Prize-winning cosmologist, has suggested that each collapse of a quantum superposition creates a moment of 'proto-consciousness.'
The Conscious Mind - Wikipedia en.wikipedia.org 2 facts
claimDavid Chalmers' account of consciousness addresses objections raised by physicist Roger Penrose regarding the many-worlds interpretation of quantum mechanics, specifically concerning why a conscious being is aware of only one alternative in a linear superposition.
claimRoger Penrose authored the essay 'Quantum physics and conscious thought', published in the book 'Essays in honour of David Bohm' in 1987.
(PDF) Quantum Mechanics and Consciousness - Academia.edu academia.edu 2 facts
A harder problem of consciousness: reflections on a 50-year quest ... frontiersin.org 1 fact
claimRoger Penrose (2004) proposed a hypothetical scenario where space exists within light, rather than light existing within space, suggesting that space might only come into being when a photon reaches an observer's eye.
Quantum Physics and Consciousness Insights | PDF - Scribd scribd.com 1 fact
referenceThe document 'Quantum Physics and Consciousness Insights' discusses several theories regarding consciousness and brain function, specifically David Bohm's implicate order, Henry Stapp's attention and quantum coherence, Roger Penrose's geometry of the universe, and Stuart Hameroff's microtubule quantum effects.
Denis Noble and Stuart Hameroff go head to head - YouTube youtube.com Apr 26, 2025 1 fact
claimStuart Hameroff is a collaborator of Roger Penrose.
Dualism (Stanford Encyclopedia of Philosophy/Winter 2016 Edition) plato.stanford.edu Aug 19, 2003 1 fact
perspectiveRoger Penrose argued that Alan Turing's halting problem has consequences similar to Gödel's theorem, suggesting that there are rational forms of thought humans can exhibit that a physical mind cannot.
Non-physicalist Theories of Consciousness cambridge.org Dec 20, 2023 1 fact
claimFriedrich Beck and John Eccles (1992) and Stuart Hameroff and Roger Penrose (2016) have proposed concrete mechanisms for how quantum coherence might occur in the brain despite environmental noise.