| Materialism/Physicalism | Only physical matter/energy exists; consciousness is reducible to brain states | Physical causation; scientific method; brain-based consciousness | Non-physical causation; souls; teleology; irreducible consciousness | Democritus, Hobbes, La Mettrie, Dennett, Churchland | Cannot explain consciousness, meaning, or information as fundamental |
| Idealism | Only mind/consciousness exists; matter is mental construction | Primacy of mind; ideas as fundamental; meaning is intrinsic | Mind-independent physical world; matter as fundamental | Berkeley, Hegel, Bradley, Kastrup | Cannot explain intersubjective physical regularities or why matter appears |
| Dualism (Cartesian) | Mind and matter are two separate substances that interact | Both mental and physical realms; subjective experience is real | Unified substance; seamless mind-body integration | Descartes, Popper, Eccles | Interaction problem: how do two substances causally relate? |
| Neutral Monism | One neutral substance underlies both mind and matter | Unity underlying apparent duality; mind-matter from same source | Irreducibility of either mind or matter to the other | Spinoza, Russell, James (early) | Vague on what the neutral substance actually is |
| Panpsychism | Consciousness is fundamental and present in all matter to some degree | Ubiquity of experience; proto-consciousness in particles | Consciousness as emergent; matter as wholly non-experiential | Leibniz, Whitehead, Chalmers, Goff | Combination problem: how do micro-experiences combine? |
| Emergentism | Higher-level properties emerge from lower-level physical processes | Novelty; causation upward; complexity creates new properties | Fundamental consciousness; strong downward causation | Mill, Alexander, Broad, Kim (reluctantly) | Explanatory gap: emergence explains correlation, not identity |
| Process Philosophy | Reality is becoming/process, not static being; events over substances | Change; relationality; experience; creativity; temporal becoming | Substances; static being; mind-matter split; determinism | Whitehead, Hartshorne, Griffin | Can become too fluid; may lose ground for objective truth |
| Classical Theism | Personal God exists as transcendent creator, sustainer, and judge | Creator-creature distinction; divine providence; objective morality | Divine identity with creation; impersonal ultimate reality | Augustine, Aquinas, Anselm, Plantinga, Craig | Problem of evil; hiddenness of God; faith-reason tension |
| Deism | God created the universe but does not intervene in it | Divine creation; rational order; natural theology | Divine intervention; miracles; personal relationship with God | Voltaire, Paine, Jefferson, Franklin | Impersonal God seems arbitrary; why create then abandon? |
| Pantheism | God IS the universe; divine = totality of nature | Divine immanence; nature as sacred; cosmic unity | Creator-creature distinction; divine transcendence; personal God | Spinoza, Bruno, Toland, Einstein (loosely) | Loses personal God; problem of evil internal to God |
| Panentheism | God contains and transcends the universe; world is in God | Divine immanence AND transcendence; world affects God | Complete divine transcendence; world as separate from God | Hartshorne, Moltmann, Clayton, Polkinghorne | Complex; may be unstable position between theism and pantheism |
| Atheistic Naturalism | Nature is all that exists; no supernatural realm or beings | Physical laws explain everything; evolution; no design required | God; souls; purpose; design; non-physical causation | Hume, Russell, Dawkins, Dennett, Harris | Cannot ground information, consciousness, or objective morality |
| Nihilism | No inherent meaning, purpose, or value exists in the universe | Freedom from illusion; radical honesty about meaninglessness | Objective meaning; moral realism; cosmic purpose; God | Nietzsche (diagnosed), Schopenhauer, Cioran | Self-refuting: claims meaning in asserting meaninglessness |
| Existentialism | Existence precedes essence; we create our own meaning | Human freedom; authenticity; responsibility for self-creation | Predetermined essence; fixed human nature; determinism | Kierkegaard, Heidegger, Sartre, Camus | No ground for choosing one meaning over another |
| Determinism (Hard) | All events are causally determined; free will is illusion | Predictability; laws of nature; no libertarian free will | Libertarian free will; ultimate moral responsibility | Laplace, Spinoza, Harris, Sapolsky | Undermines rationality and moral responsibility |
| Eliminative Materialism | Mental states do not exist; folk psychology is false | Neuroscience; behavior explanations without mental vocabulary | Beliefs; desires; intentions; all mental vocabulary | Churchland, Stich, Ramsey | Self-refuting: uses beliefs to deny beliefs exist |
| Functionalism | Mental states are defined by functional roles, not substance | Multiple realizability; AI consciousness possible | Substrate-dependence of mind; biological necessity for consciousness | Putnam, Fodor, Armstrong, Lewis | Absent qualia problem; Chinese Room; substrate matters |
| Epiphenomenalism | Mental events exist but have no causal power | Consciousness exists; physical world is causally closed | Mental causation; interactionism; free will | Huxley, Jackson (early), Chalmers (entertains) | Consciousness becomes inexplicable epiphenomenon |
| Buddhist Metaphysics | No-self (anatta); reality is impermanent (anicca); dependent origination | Interconnection; impermanence; cessation of suffering possible | Permanent self; creator God; inherent existence | Buddha, Nagarjuna, Vasubandhu | No ultimate ground; why something rather than nothing? |
| Advaita Vedanta | Only Brahman (pure consciousness) is real; world is maya (illusion) | Pure consciousness; liberation (moksha); unity with Brahman | Reality of individual selves; world as ultimately real; duality | Shankara, Ramana Maharshi, Nisargadatta | If world is illusion, why does it appear? Brahman and maya relation unclear |