Philosophy of Science Skill

Master the philosophical foundations of science: What is scientific method? What is explanation? Are scientific theories true?

Core Questions

Scientific Method

The Problem of Induction

Hume's Problem: How do we justify inductive inference?

• Past regularities don't logically guarantee future ones
• Cannot use induction to justify induction (circular)
• Yet science relies on induction

Falsificationism (Popper)

POPPER'S FALSIFICATIONISM
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DEMARCATION CRITERION
├── Science: Falsifiable claims
├── Pseudo-science: Unfalsifiable
└── Examples: Astrology, Freud (unfalsifiable)

METHOD
├── Bold conjectures
├── Severe tests
├── Refutation → new conjecture
└── Corroboration ≠ confirmation

KEY IDEA:
We never confirm theories
We only fail to falsify them
Asymmetry: One counterexample refutes

Problems:

• Theories rarely abandoned on single refutation
• Auxiliary hypotheses can absorb refutation
• No purely observational test

Paradigms (Kuhn)

KUHN'S STRUCTURE OF SCIENTIFIC REVOLUTIONS
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NORMAL SCIENCE
├── Work within paradigm
├── Puzzle-solving
├── Anomalies accumulate
└── Paradigm defines problems, methods

CRISIS
├── Too many anomalies
├── Alternative paradigms emerge
├── Debate between paradigms
└── Incommensurability

SCIENTIFIC REVOLUTION
├── Paradigm shift
├── Not cumulative progress
├── New worldview
└── Gestalt switch

EXAMPLES:
├── Ptolemy → Copernicus
├── Newton → Einstein
└── Phlogiston → Oxygen

Scientific Explanation

Deductive-Nomological (D-N) Model

D-N MODEL (Hempel)
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EXPLANATION STRUCTURE:
L₁, L₂, ... Lₙ  (Laws)
C₁, C₂, ... Cₙ  (Conditions)
─────────────────
E              (Explanandum)

REQUIREMENTS:
├── Deductively valid
├── Laws are essential
├── Empirically testable
└── True premises

EXAMPLE:
All metals expand when heated.
This is metal.
This was heated.
∴ This expanded.

Problems:

• Symmetry problem (flagpole and shadow)
• Irrelevance problem
• Statistical explanation

Causal-Mechanical Model

• Explanation = tracing causal mechanism
• Not just subsumption under laws
• Mechanisms explain, not just correlate

Unificationism

• Explanation = unifying diverse phenomena
• Fewer patterns explaining more
• Newton unified celestial and terrestrial motion

Scientific Realism

The Debate

Scientific Realism:

• Mature scientific theories are approximately true
• Theoretical entities (electrons, genes) exist
• Science aims at truth

Anti-Realism (Instrumentalism):

• Theories are useful tools
• Theoretical terms don't refer
• Science aims at empirical adequacy

Arguments for Realism

No Miracles Argument:

• Science's success would be miraculous if theories weren't true
• Best explanation of predictive success is truth
• "The only philosophy that doesn't make science a miracle"

Arguments Against Realism

Pessimistic Meta-Induction:

• Past "successful" theories were false
• Caloric, phlogiston, ether
• Current theories probably also false

Underdetermination:

• Multiple theories compatible with same evidence
• Evidence doesn't uniquely determine theory
• Why think ours is true?

Structural Realism

Epistemic: We can know structure, not nature Ontic: Structure is all there is

Reduction and Emergence

Reductionism

• Higher-level sciences reducible to lower
• Biology → Chemistry → Physics
• Unity of science thesis

Emergence

• Some properties not reducible
• Whole greater than parts
• Consciousness? Life?

Multiple Realizability

• Same higher-level state, different lower-level realizations
• Pain in humans ≠ pain in octopi (neurally)
• Blocks type-identity reduction

Key Debates

Demarcation

• What makes something science?
• Falsifiability? Paradigms? Method?
• Is demarcation possible?

Theory Choice

• Empirical adequacy
• Simplicity, parsimony
• Explanatory power
• Fruitfulness

Values in Science

• Value-free ideal achievable?
• Social influences on science
• Science studies, feminist philosophy of science

Key Vocabulary

Integration with Repository

Related Themes

• thoughts/knowledge/: Scientific knowledge
• thoughts/consciousness/: Neuroscience methodology