1.4: Wittgenstein & Logical Positivism

Ludwig Wittgenstein (early)

Philosopher who aimed to determine the limits of meaningful language and thought.

World (Wittgenstein)

The world consists of facts, not things.

Facts

Combinations of objects in a specific state of affairs.

Propositions

Sentences that picture states of affairs in the world.

Language-world relation

A proposition is meaningful if it mirrors a possible state of affairs.

Picture theory of meaning

Meaning arises when a proposition pictures reality.

Meaningful proposition

A statement that can be true or false by comparison with reality.

Nonsense (Wittgenstein)

Statements that cannot picture reality.

Ethics and metaphysics (Wittgenstein)

Ethical, aesthetic, and metaphysical claims are meaningless in a strict sense.

Limits of language

The limits of language determine the limits of what can be meaningfully thought.

Philosophy (Wittgenstein I)

Clarifies language and shows what can be said meaningfully.

Science and meaning

Only empirical and logical statements are meaningful.

Tractatus

A work that inspired Logical Positivism.

Logical Positivism

Movement combining empiricism and logic to define meaningful science.

Vienna Circle

Group of philosophers who developed Logical Positivism.

Aim of Logical Positivism

Separate science from metaphysics using a criterion of meaning.

Verification principle

A statement is meaningful only if it is empirically verifiable or analytically true.

Analytic statements

True by definition, e.g., logic and mathematics.

Synthetic statements

Truth depends on observation.

Metaphysics (positivism)

Claims that are meaningless because they are not verifiable.

Demarcation criterion (positivism)

Verifiability separates scientific from non-scientific statements.

Meaningful scientific statement

A claim that can be tested by observation.

Meaningless statement

A claim that cannot be empirically or logically verified.

Role of philosophy (positivism)

Analysis and clarification of scientific language.

Protocol sentences

Basic observation statements describing immediate experience.

Inductive buildup (positivism)

Scientific knowledge is built from observation to theory.

Theory-ladenness

Observation is influenced by prior theories and concepts.

Problem of verification (general laws)

Universal laws cannot be fully verified.

Self-refutation problem

The verification principle is not itself verifiable.

Structure of science (positivism)

Scientific knowledge should be expressed in formal logical language.

Observational terms

Terms referring to measurable phenomena.

Theoretical terms

Terms referring to unobservable entities.

Unity of science

All sciences should share the same logical-empirical structure.

Reductionism

Scientific statements should be reducible to observation statements.

Anti-metaphysical stance

Metaphysical, ethical, and aesthetic claims are excluded from science.

Emotive meaning (Ayer)

Non-verifiable statements may express emotions or attitudes.

Popper’s criticism

Verification encourages confirmation bias.

Falsification

A theory is scientific if it can be proven false in principle.

Popper vs positivism

Falsifiability replaces verifiability as the demarcation criterion.

Limits of logical reduction

Not all language can be reduced to formal logic.

Decline of Logical Positivism

Collapsed due to internal and external criticism.

Legacy of Logical Positivism

Influenced debates on scientific method, meaning, and demarcation.