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David Lewis

ISBN: 978-0-631-22495-2 January 2001 Wiley-Blackwell 168 Pages


Counterfactuals is David Lewis' forceful presentation of and sustained argument for a particular view about propositions which express contrary to fact conditionals, including his famous defense of realism about possible worlds.


1. An Analysis of Counterfactuals.


Strict Conditionals.

Variably Strict Conditionals.

The Limit Assumption.

'Might' Counterfactuals and Outer Modalities.

Impossible Antecedents.

True Antecedents.

Counterfactual Fallacies.


2. Reformulations.

Multiple Modalities.

Propositional Quantifiers.

Comparative Similarity.

Similarity Measures.

Comparative Possibility.


Selection Functions.

The Selection Operator.

3. Comparisons.

The Metalinguistic Theory: Implicit Premisis.

The Metalinguistic Theory: Factual Premises.

The Metalinguistic Theory: Laws of Nature.

Stalnaker's Theory.

4. Foundations.

Possible Worlds.


5. Analogies.

Conditional Obligation.

'When Next' and 'When Last'.

Contextually Definite Descriptions.

6. Logics.

Completeness Results.

Decidability Results.

Derived Modal Logics.

Appendix: Related Writings by David Lewis.


"'Contrary-to-fact conditionals have provided logical analysts with fascinating puzzles. (This book) has a unitary theme presented clearly and attractively for the most part with only the unavoidable minimum of formal apparatus. The theme is pursued confidently and relentlessly without evasions or qualifications." Times Literary Supplement

"This is an excellent book. It combines shrewd philosophical sense with a fine technical expertise. The statement of views is concise and forthright." Kit Fine, Mind

"This essay is a virtuoso performance." British Journal for the Philosophy of Science

"Beautifully and lucidly written and full of clever ideas. It contains very many philosophical insights and comparisons." J. J. C. Smart, Australasian Journal of Philosophy

  • Written by one of the most distinguished and influential philosophers alive today.
  • Cuts across core issues in logic, metaphysics, language, and epistemology.
  • A Contemporary classic.
  • Counterfactual statements are a perennial subject of interest in philosophical logic.