The history of western music owes much to the Baroque period (1580-1750). One can observe the appearance of many elements that remain a permanent part of musical compositions today. In fact, this period is especially marked by the birth of the first opera: music conquers the theatricality. The musicians start searching the expression of the passions of the human soul in music (something often banned in the Middle Ages and barely initiated in the Renaissance). Finally, the instrumental music will grow considerably throughout the seventeenth century to take precedence over vocal music, hitherto dominant. Many new forms will see the day, alongside more traditional forms. Italy and France are the engines of these aesthetic changes. Music provides a representation of certain forms of transcendence that knowledge has never been and will never be a knowledge. The music is an open system: it is addressed first to each individual. In addition, it is a system referred, and which thus creates its own semantics. Which tends to prove that the ontology of the musical work is reflected well on these two plans that aesthetic philosophies are still able to distinguish: a plane of immanence where the artwork is means itself and identifies its object, and a plan of transcendence where it overflows this object, where it has more object and where it merely be report to the world. If development of the language and its evolution into a formal system formed the main basis of scientific development, the art also has the power to exert influence on our knowledge and our forms of communication? Symbolic code, art produces sometimes consciously, signs, General or specific, overt or tangible, who plays such as those of any language. Vincent d'Indy, in the introduction to his musical composition course, suggests the power of communication. Considers that from a subjective point of view one can adopt the definition given by Tolstoy for whom "art is human activity through which a person can voluntarily, and using external signs, communicate to others the sensations and feelings she experiences herself."The music if it assimilates it to such a will, becomes actually power a symbolic code. This approach refers to a narrow definition of basic elements in music. Its functioning depends more than listed or voluntarily designated signal. While acknowledging the importance of functional correspondence, it seems difficult to acquiesce