What Are the Metaphysical Issues?  Metaphysics: questions about the nature of reality  Nature of ultimate reality permanence and change appearance and reality  Nature of human reality mind-body problem freedom and determinism

Metaphysical Positions  Monism Materialism Idealism  Dualism

Conceptual Tools for Metaphysics  Simplification of complexity Ockham's razor  Inference to the best explanation used by both science and metaphysics

Ontology  Questions about what is most fundamentally real  Fundamental reality that upon which everything else depends that which cannot be created or destroyed

Metaphysical Categories  Things that are not real: eliminativist strategy  Realities reducible to more fundamental realities: reductionist strategy  Things that are fundamentally real

Plato’s Metaphysics  Nonphysical realities: Platonic Forms  Degrees of reality  Allegory of the cave

Propositions of the Mind- Body Problem  The body is a physical thing  The mind is a nonphysical thing  The mind and body interact and causally affect one another  Nonphysical things cannot causally interact with physical things  These four statements cannot all be true

Positions on the Mind-Body Problem  Mind-body dualism Interactionism Parallelism Occasionalism  Physicalism Identity theory (reductionism) Eliminativism  Functionalism

Descartes’s Arguments for Mind-Body Dualism  Principle of the nonidentity of discernibles  Argument from doubt Discourse on the Method  Argument from divisibility  Argument from consciousness Meditations on First Philosophy

The Cartesian Compromise Division of reality Science’s authority in the physical realm Religion’s authority in the spiritual realm Interactionism

Physicalism: An Alternative to Dualism  Four problems of dualism: Where is the mind-body interaction? How does the interaction occur? Conservation of energy? Success of brain science?

The Positive Case for Physicalism  Correlation between mental events and brain states  Consciousness may be a by-product of low-level physical processes

Forms of Physicalism  Identity theory, or reductionism Mental events are identical to brain events Brain research will answer all questions about the mind  Eliminativism Labels traditional psychological theories as folk psychology No beliefs or desires, only brain states and processes

Functionalism  Minds are constituted by a certain pattern or relation between the parts of a system  Minds have multiple realizability  Mental states are defined in terms of their causal role (how they function)

Artificial Intelligence  Can computers think?  Turing test  Strong AI thesis: an appropriately programmed computer can think  Weak AI thesis: a computer can only simulate mental activities

Issues of Freedom and Determinism  How do nature/nurture, heredity/ environment affect us ? consider identical twins, separated at birth  What is the origin of our actions?  What implication does determinism have for moral responsibility?

Types of Freedom  Circumstantial ability to do what we choose freedom from external forces  Metaphysical free will relates to our internal condition, not external forces  Most philosophy is concerned with metaphysical freedom

Positions on Freedom  Determinism  Libertarianism  Incompatibilism  Hard determinism  Compatibilism

Hard Determinism  Problems with libertarianism  Positive arguments for determinism  Denial of the possibility of moral responsibility

Objections to Libertarianism  Conflicts with the scientific world view  Requires the problematic notion of uncaused events  Fails to explain that we can influence other people's behavior

The Positive Case for Determinism  1. Every event, without exception, is causally determined by prior events  2. Human thoughts and actions are events  3. Therefore, human thoughts and actions are, without exception, causally determined by prior events

Determinist Thinkers  Spinoza pantheism free will is an illusion  B.F. Skinner radical behaviorism reduction of all mental terms to scientific statements about behavioral probabilities

Tenets of Libertarianism  We are not determined  We do have freedom of the will  We have the capacity to be morally responsible for our actions

Objections to Determinism  Determinism makes an unwarranted generalization from a limited amount of evidence  Determinism undermines the notion of rationality  Determinism confuses methodological assumptions of science with metaphysical conclusions

Types of Antideterminism  Indeterminism Some events are uncaused  Agency theory Event-causation Agent-causation  Radical existential freedom Jean-Paul Sartre

Arguments for Libertarianism  Argument from introspection  Argument from deliberation  Argument from moral responsibility

Compatibilism  Soft determinism  We are both determined and morally responsible for our actions  Voluntary actions take place when the determining causes reside within the agent, not externally

Hierarchical Compatibilism (Frankfurt)  First-order desires  Second-order desires  Second-order volitions