David Lewis 
Counterfactuals [PDF ebook] 

Preface.
Acknowledgements.
1. An Analysis of Counterfactuals.
Introduction.
Strict Conditionals.
Variably Strict Conditionals.
The Limit Assumption.
‘Might’ Counterfactuals and Outer Modalities.
Impossible Antecedents.
True Antecedents.
Counterfactual Fallacies.
Potentialities.
2. Reformulations.
Multiple Modalities.
Propositional Quantifiers.
Comparative Similarity.
Similarity Measures.
Comparative Possibility.
Cotenability.
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.
Similarity.
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.
Index.

David Lewis (1941- 2001) was Professor of Philosophy at Princeton University. His publications include Convention (reissued by Blackwell 2002), On the Plurality of Worlds (reissued by Blackwell, 2000), Parts of Classes (1991), and of numerous articles in metaphysics and other areas. Many of his writings are available in his Collected Papers.