For Etienne Bonnot de Condillac, music was a solution to a problem. The problem arose in connection with the radical empiricism he advocated in his 1746 Essai sur l'origine des connaissances humaines, which sought to derive all knowledge from sensation. Stated simply, the problem was one of explaining how such sensory information could be organized into knowledge. Music – and in particular the theoretical account of musical organization proposed by Jean-Philippe Rameau – offered a solution, for it provided a link to the passions that motivated the formation of knowledge as well as a rational structure through which knowledge could be organized.

As he surveyed the basic capacities upon which knowledge was grounded Condillac noted that humans shared most of them with brute animals. What humans had that animals did not was a memory guided and facilitated by what Condillac called instituted signs. The two other sorts of signs Condillac recognized, accidental signs and natural signs, were shared with animals: accidental signs are simply the perceptual traces of the objects we behold; natural signs are the involuntary cries associated with passions such as joy or grief. Instituted signs, by contrast, are wholly volitional: they are signs that we choose to represent some aspect of knowledge. Once knowledge is represented it can be remembered and made available for contemplation – it becomes truly knowledge, rather than transitory sensory information.