The work studies the nature of sound, consonance, and dissonance through a mathematical viewpoint, presenting music theory as a bridge between abstract mathematics and human perception, and marking one of the first systematic attempts to study musical aesthetics through scientific principles. Descartes wrote this treatise during his stay in Breda, but it was only printed after his death.
It discusses the relationship between music and mathematics, and how music can be understood through mathematical principles. This work influenced later discussions of the mathematical foundations of music. The text explains that music has the ability to arouse different passions by using variations in time, intensity, and the arrangement of sounds. Music can recall feelings of sadness, joy, or fear, and these emotional effects are attributed to harmony, rhythm, and proportion in the composition of sounds.
Here he breaks down the "key properties of sound" such as pitch (high or low) and duration (time), are analyzed to show how they influence the listener's emotional response. It explains the weight of proportion, symmetry, and variety in creating pleasing sounds. Descartes also studies concepts such as consonance, dissonance, and the division of sounds into intervals (octaves, fifths, and thirds), giving attention to the mathematical relationships that form the basis of harmony.
This edition contains an Afterword from the translator, as well as a timeline of Descartes' life and summaries of each of his works.