This is the fourth volume in the "Contemporary Philosophy" series co-ordinated by Stefano Poggi. The series attempts to deal with the history of contemporary thought in an innovative manner, with an approach centred not so much on single philosophers' works as on the evolution of key concepts which comprehend the bases of philosophical reflection. The first three volumes, published at the beginning of the year 2000, were "Identity and Consciousness" (D. Sparti), "Sensation, Perception, Concept" (P. Spinicci) and "Being and Its Meanings" (F. Toccafondi). The topics of the next volumes will be "A Priori Categories" (M. Ferrari) and "The Object and the Meaning of History" (G. Cacciatore). The opposition between liberty and necessity, or determinism, underlies all modern philosophy, even if in ancient Christian doctrines the issue of free will was already a central topic. The author starts off with the first modern philosophical system, that is to say Descartes', and then tracks how philosophical positions have meandered between the two concepts in Kant, German idealism, philosophical psychology, the various positivist and materialist currents (all founded on a deterministic notion of reality), spiritualism, Schopenhauer and Nietzsche, existentialism, pragmatism and various twentieth century philosophies (including those of Berdyaev, Foucault, and the Frankfurt School), and concludes with scientific debate.

Massimo Mori teaches History of Modern Philosophy in the Faculty of Letters at the University of Turin.