--- title: David Chalmers --- David Chalmers is the philosopher who gave the modern science of consciousness its defining question. In 1995 he drew a sharp line between the "easy problems" of the mind — how the brain discriminates, integrates information, reports its states — and what he named the **hard problem**: why all that processing should be accompanied by inner experience at all. The phrase stuck, and the distinction now organizes the entire field. He is no fringe figure — a University Professor at NYU, co-founder of the philosophy database PhilPapers, and among the most eminent philosophers of mind alive — which is precisely what gives his conclusion its weight: that consciousness may not be reducible to the physical, and might have to be treated as a fundamental feature of reality. ## The hard problem Chalmers' central move is a division of labour. The "easy" problems — explaining the brain's functions — are easy only in that we know, in principle, how to attack them with the methods of cognitive science. The **hard problem** is the problem of experience itself: *why is the performance of all these functions accompanied by an inner life?* A complete mechanistic account of the brain still seems to leave that question open — the "explanatory gap." The full argument is set out in , in his landmark 1995 paper "Facing Up to the Problem of Consciousness." ## Zombies and the limits of physics His sharpest tool is the **philosophical zombie**: imagine a being physically identical to you down to the last molecule, behaving exactly as you do, but with no inner experience whatsoever — nobody home. Chalmers argues that such a creature is at least conceivable, and that if it is even metaphysically possible, then the complete physical truth about the world does not logically fix the facts about experience — so consciousness is something "over and above" the physical. His own positive view is **naturalistic dualism**: not a soul or a Cartesian second substance, but a *property* dualism, on which experience is a basic feature of the world alongside mass and charge, tied to physical processes by lawlike bridging principles. He is also seriously, if tentatively, drawn to **panpsychism** — the idea that experience goes all the way down. ## Worlds within worlds Chalmers' restless range carries him well beyond consciousness. In *Reality+* (2022) he argues that virtual worlds are *genuinely real* and that the simulation hypothesis is a claim about what reality is made of rather than a reason for doubt — explored in . And with Andy Clark he co-authored the philosophers' "extended mind" thesis (1998): the proposal that the mind reaches into the notebooks and devices we think *with* — a claim about cognitive offloading that is distinct from the field-based "extended mind" discussed elsewhere on this wiki. ## Where he stands The honest picture is a striking one. The hard problem itself is *widely granted* — most philosophers take it seriously — even as a majority remain physicalists who expect it to yield to science eventually. Chalmers' anti-physicalist conclusion is the minority side: rigorously argued, much-debated, and resisted above all by Daniel Dennett, who regards the whole hard problem as a seductive illusion. That his eminence and his minority metaphysics sit comfortably together is part of what makes him interesting — and he even co-runs the global survey that documents the field's divide. ## Sources & talks His TED talk on the puzzle of experience: A longer conversation on consciousness and science: **Primary sources:** David Chalmers, ["Facing Up to the Problem of Consciousness," ](https://consc.net/papers/facing.html)[*Journal of Consciousness Studies*](https://consc.net/papers/facing.html)[ 2(3):200–219 (1995)](https://consc.net/papers/facing.html) · *The Conscious Mind* (Oxford, 1996) · *Reality+: Virtual Worlds and the Problems of Philosophy* (W. W. Norton, 2022) · and his open archive at [consc.net](https://consc.net/).