A classic theory of sound cannot prevail when our present world is utterly traversed and inhabited, in an unprecedented way, by sound. In this way, the present book intends to carry out a philosophical exercise based on the restlessness that is born from the experience of this contemporary sound life. This exercise links sounds to a consideration of the event that is totally independent of anything else. It takes as a permanent example the proposals of John Cage, who always sought to lend an ear to the activity of sound, knowing that in no case did listening consist in appropriating sounds or appropriating with sounds. Strictly speaking, there is no ownership, appropriation, or disappropriation of sounds: pure freedom of the event, pure freedom of the experience of listening. At least, that is the horizon, the silence.