Throughout the history of western music, composers have relied on “outside-of-time” structures which have served as musical “prime matter” until the moment of their temporal inscription. These structures have traditionally been the scales, rhythmic values, formal schemes, harmonic rules, etc., that composers have employed over and over again. They are to the composer what marble is to the sculptor or colors are to the painter. The advent of computer technology has opened new avenues that allow composers to develop new structures and enlarge their creative horizon. I started my musical training at a very early age, and at the same time I had a lot of scientific curiosity. As soon as I had my first computer (a Commodore 64), I started to experiment, to establish relationships between scientific processes and the world of sound. To date, and following the footsteps of I. Xenakis (although from a different aesthetic perspective), my compositions have always been informed, to a lesser or greater degree, by some underlying scientific idea, and this task can hardly be achieved without computation. Furthermore, today, computer-composers open the possibility to access and use an ever-growing repository of musical material goes a step forward in this direction. And this raises many questions, some of them of a deep philosophical ground.