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Thought experiments

Philosophical scenarios — not empirical studies — used to test intuitions about consciousness, mind, perception, and meaning. Distinct from experiments, which judges studies on replication. Thought experiments are judged on dialectical force: what intuition do they pump, what position do they support, what counter-arguments survive?

Schema

Each entry: scenario (original-language form where useful) — origin (author / source). What it argues, then its role in the KB. Links: cross-refs.

No replication status — these aren't empirical claims. Where a thought experiment is contested or its author later revised, the take notes it.

Consciousness, qualia, and the mind–body problem

  • Plato's Cave — Plato, Republic Book VII (~375 BCE). Prisoners chained facing a wall see only shadows of objects passing behind them and take the shadows for reality. Ordinary perception stands to true reality as shadows stand to objects; philosophy is the ascent out of the cave into knowledge of the forms. Foundational metaphor for the appearance vs. reality distinction that runs through every consciousness debate — including the modern predictive-processing claim that perception is a controlled hallucination, and Metzinger's PSM as a transparent self-model. The cave keeps coming back because the geometry is the same. Links: Metzinger, predictive coding.
  • Zhuangzi's butterfly dream (莊周夢蝶 / Сон Чжуан-цзы о бабочке) — Zhuangzi (Zhuang Zhou), Zhuangzi, "Discussion on Making All Things Equal" (~4th century BCE). Zhuangzi dreams he is a butterfly fluttering happily, unaware of being Zhuangzi. He wakes, and can no longer tell whether he is a man who dreamed of being a butterfly, or a butterfly now dreaming of being a man. Sister case to Plato's Cave on the appearance vs. reality axis, but pointed at personal identity and continuity of consciousness across states rather than at perception. Anchor reference for the KB's Phenomena layer (dreams, lucid states) and for any claim about diachronic identity of the self — including Metzinger's PSM, where the same self-model is run in dream and waking. Links: Plato's Cave, Metzinger, the Phenomena layer.
  • Mary's Room (the knowledge argument) — Frank Jackson, Epiphenomenal Qualia (1982); refined in What Mary Didn't Know (1986). Mary is a colour scientist raised in a black-and-white room who knows every physical fact about colour vision. When she leaves the room and sees red for the first time, does she learn something new? Jackson argues: yes — and therefore physicalism is false (knowledge of all physical facts ≠ knowledge of all facts). The canonical argument against physicalism about consciousness; cited by Chalmers for the hard problem and contested by Dennett (Mary learns a know-how, not a new fact) and Tye (representationalism). Note: Jackson himself abandoned the anti-physicalist conclusion in Mind and Its Place in Nature (~1998), which is awkward for everyone who still cites it. Links: Chalmers, Dennett, hard problem, qualia.
  • The Chinese Room — John Searle, Minds, Brains, and Programs (Behavioral and Brain Sciences, 1980). A person who knows no Chinese sits in a room with a rule book and manipulates Chinese symbols according to the rules, producing correct Chinese responses to Chinese questions. The room as a whole passes a Turing test in Chinese — but no understanding is happening. Therefore: syntax (rule-following) is not sufficient for semantics (understanding); computation alone cannot produce a mind. The flagship argument against strong AI / computational functionalism. Pairs with Searle's Mind in the books layer and his biological-naturalism position. Heavily contested — the "Systems reply" (the room as a whole understands), "Robot reply" (embodied Chinese Room would understand), "Brain Simulator reply", "Other Minds reply" all live in the dialectic. Direct counterweight to Dennett's multiple-drafts and Hawkins's memory-prediction views in the KB. Links: Searle's Mind, Searle, Dennett, biological naturalism.
  • Philosophical zombies (p-zombies) — Term: Robert Kirk (1974); canonical modern argument: David Chalmers, The Conscious Mind (1996). A being physically and functionally identical to a conscious human — same brain states, same behavior, same verbal reports — but with no phenomenal experience. Nothing it is like to be them. Chalmers's argument: if p-zombies are conceivable, then phenomenal consciousness is not entailed by physical / functional facts, so physicalism is false. The metaphysical sibling of the Chinese Room: Chinese Room targets understanding without semantics, p-zombies target behavior without experience. Chalmers's flagship blade against Dennett-style functionalism, and the most direct expression of we can't verify others are conscious in the KB. Heavily contested — opponents argue zombies aren't actually conceivable, or that conceivability ≠ possibility. Links: Chalmers's The Conscious Mind, Chinese Room, problem of other minds.

When a thought experiment earns its own page

Once the dialectic around a scenario accumulates more than an entry's worth of replies and counter-replies — extract to thought-experiments/<slug>.md and replace the entry with a link. The Chinese Room is the obvious first candidate.