  This article has been written, in a slightly different version, as an
introductory chapter for the book collecting the essays of theoretical
physicist Gerard 't Hooft, philosopher Emanuele Severino, and theologian Piero
Coda, and inspired by the talks the three authors made as keynote speakers at
the conference "Determinism and Free Will", held at the Cariplo Foundation
Congress Center in Milan on May 13, 2017.
