John Morrison
Affiliation
I am a professor of philosophy at Barnard College, Columbia University. I am an affiliate of Barnard's Neuroscience and Behavior Department, Columbia's Mind Brain Behavior Institute, and Columbia's Center for Theoretical Neuroscience. I am also a mentor in Columbia's Neurobiology and Behavior Graduate Program. My research has been supported by the National Endowment for the Humanities, National Science Foundation, Mellon Foundation, and Data Sciences Institute. I am an editor of the Journal of Philosophy. I led the effort to create the cognitive science program at Barnard and Columbia, and served as Barnard's founding director.
Teaching
In the fall I will teach Introduction to Cognitive Science with Chris Baldassano and one section of the senior project seminar for cognitive science majors. In the spring I will teach a seminar on cognitive interpretations of neural systems for the Neurobiology and Behavior Graduate Program. It will also be open to PhD students in philosophy as well as cognitive science and philosophy majors.Research
My research is primarily in the philosophy of mind (esp. cognitive neuroscience and AI) and the history of modern philosophy (esp. the seventeenth century).
I am currently working on two projects. The first is an attempt to understand neural systems, biological and artificial, from an abstract perspective. Physics and economics provide helpful models of what I'm aiming for. When trying to understand a thermodynamic system, it's often better to abstract away from the activities of individual molecules, and instead focus on more global features, such as pressure and temperature. When trying to understand an economic system, it's often better to abstract away from the activities of individual consumers, and instead focus on more global features, such as inflation and gross domestic product. Likewise, when trying to understand neural systems, it's often useful to abstract away from the activities of individual neurons, and instead use the central concepts of cognitive science, such as representations and algorithms. Unfortunately, whereas we have precise and uniform definitions of pressure, temperature, inflation, and gross domestic product, there are no widely accepted definitions of representation and algorithm in terms of neural activity. The overall goal of this project is a framework precise enough to settle when these concepts genuinely apply to a neural system.
This project builds on past research on conscious perception. In one line of research, I argued that our conscious perceptions involve probabilities. I called this view Perceptual Confidence. I have expanded my focus to include unconscious neural representations and the algorithms that rely on them. In another line of research, I argued that our conscious perceptions of color properties, such as redness, depend on our representations of the differences and similarities between objects, thereby reversing the traditional order of explanation. I called this view Perceptual Structuralism. I am now expanding my focus to include unconscious neural representations of other properties, such as orientation.
The second project is about the foundations of Spinoza's metaphysics. It's an attempt to unravel his claims about minds, bodies, God, and their essences. In past research, I argued for new interpretations of Spinoza's basic notions, namely causation, conception, and inherence. I also argued that Spinoza would reject the Indiscernibility of Identicals in response to a puzzle of identity over time, and that this is the key to understanding his view of the mind's relation to the body. I am now trying to understand his view of essences.
Contact
jmorrison [at] barnard.eduCV
Postdocs
Nedah Nemati (2023-2025)
Raphael Gerraty (2019-2021)
PhD Students
Aaron Wang (advisor)
Weiming Sheng (advisor)
Matthew Morgado (committee)
Lisa Clark (advisor)
Andrew Richmond (advisor, PhD 2022)
Natalie Hannan (committee, PhD 2021)
Simon Brown (committee, PhD 2020)
Jorge Morales (advisor, PhD 2018)
Jeremy Wolos (advisor, PhD 2016)
Philosophy of Cognitive Neuroscience
"Using Transfer Learning to Identify a Neural System's Algorithm,"
with Niko Kriegeskorte and Benjamin Peters (under review, first author),
draft,
video
"Representation in the Hippocampus: Clarifying the Disagreement,"
with Abhishek Shah (draft circulating, equal contribution)
"Source Invariance and Probabilistic Transfer: A Testable Theory of Probabilistic Neural Representations,"
with Sam Lippl, Raphael Gerraty, and Niko Kriegeskorte (draft circulating, co-last author),
preprint
"Learning to Count Interferes with Proportional Reasoning in Convolutional Neural Networks,"
with Miriam Rosenberg-Lee (accepted at MCLS 2026, equal contribution)
"Revisiting Iconic Memory With a New Paradigm,"
with Gal Vishne, Miranda Ye, Zoe Haynes, Nick Turk-Browne, and Mike Shadlen (accepted at VSS 2026, co-last author)
"Othello-GPT Does Not Have a World Model: General Lessons for Attributing World Models to Neural Systems,"
with Mouad Oulouali and Teo Maayan (submitted to conference, first author)
"Algorithms for Neural Networks"
"Representations for Neural Networks"
"Flavors of Abstraction: Comparing Methods for Identifying Algorithms in Neural Networks,"
with Tiannan Wang, Amir Zur, Atticus Geiger, and Benjamin Peters (last author)
Probabilities and Perception
"Perceptual Confidence,"
Analytic Philosophy (2016), final *Winner of the 2015 Sanders Prize in Philosophy of Mind
"Perceptual Confidence and Categorization,"
Analytic Philosophy (2017), final
"Third-Personal Evidence for Perceptual Confidence,"
Philosophy and Phenomenological Research (2024), final
Perceptual Structuralism
"Colour in a Physical World,"
Mind (2012), final, appendix
"Anti-Atomism about Color Representation,"
Noûs (2015), final
"Triangulating How Things Look,"
Mind & Language (2015), final
"Perceptual Variation and Structuralism,"
Noûs (2020), final
"Perceptual Variation and Relativism,"
Epistemology After Sextus Empiricus (2020), Vogt & Vlastis (eds.), final, appendix
"Perceptual Variation and Ignorance,"
Synthese (2021), final
Early Modern Metaphysics
"Conception and Causation in Spinoza's Metaphysics,"
Philosophers' Imprint (2013), final
"Restricting Spinoza's Causal Axiom,"
Philosophical Quarterly (2015), final
"Truth in the Emendation,"
The Young Spinoza, Melamed (ed.) (2015), final
"Two Puzzles about Thought and Identity in Spinoza,"
Cambridge Critical Guide to Spinoza's Ethics, Melamed (ed.) (2017), final
"Spinoza on Numerical Identity and Time,"
Blackwell Companion to Spinoza, Melamed (ed.) (2021), final
"Descartes on Numerical Identity and Time,"
The Australasian Journal of Philosophy (2022), penultimate, final
"Spinoza on Mind, Body, and Numerical Identity,"
Oxford Studies in Philosophy of Mind (2022), final
"Three Medieval Aristotelians on Numerical Identity and Time,"
Oxford Studies in Medieval Philosophy (2022),
final
"Seven Challenges for Garrett's Interpretation of Mind-Body Identity,"
Naturalism in Early Modern Philosophy, Garrett and Cottrell (eds.), Oxford University Press (forthcoming), penultimate
Reviews
Review of Valtteri Viljanen's Spinoza's Geometry of Power
British Journal for the History of Philosophy (2013), final
Review of De Rosa's Descartes and the Puzzle of Sensory Representation (with Elliot Paul), Mind (2014), final