David Lewis
1941 – 2001 · Oberlin, Ohio; Princeton
A systematic metaphysician who argued that every possible world is as real as ours, and wrote classic papers on time travel and personal identity.
Key ideas
Lewis is best known for modal realism: talk of what is possible is talk of other possible worlds, and those worlds are just as concrete as the actual one. We call our world actual only because we are in it. Few accepted the view, but many admired how much it explained.
His 1976 paper 'The Paradoxes of Time Travel' argued that time travel is logically consistent: a time traveller cannot change the past, but can be part of it, and the grandfather paradox only shows what will not happen, not what cannot be attempted.
He also defended a four-dimensional view of persons, offered the ability hypothesis as a physicalist answer to Mary's room, and wrote on counterfactuals, causation, convention and decision theory.
Life, briefly
Lewis grew up in Oberlin, Ohio, studied at Swarthmore and Harvard, and taught at UCLA and then at Princeton from 1970 until his death. He spent long periods in Australia, which he loved. He suffered from severe diabetes for most of his life and died at sixty.
Major works
- Convention (1969)
- Counterfactuals (1973)
- The Paradoxes of Time Travel (1976)
- On the Plurality of Worlds (1986)
- Philosophical Papers (1983, 1986)
Appears in
Further reading
- EncyclopediaStanford Encyclopedia of Philosophy: David Lewis
- WikipediaDavid Lewis (philosopher)