David K. Lewis, born 1941, set the modern technical doorway into fictional truth. In his model, we can say things like “in the Sherlock Holmes stories, Holmes lived at 221B Baker Street” without pretending Holmes was a historical person. That distinction helps separate empirical event truth from truth inside a fictional construction.

His work and paper “Truth in Fiction,” asks what it means for a statement to be true inside a fictional world, often framed as “in fiction f, Φ.” Lewis gave us the modern analytic version of the question Aristotle opened: fiction is invented, but it can still have truth conditions.