This PhD thesis proposes a reading of three passages about music in the Critique of Judgement written by Kant in order to establish their connection with Formalism : the example of the sound in § 14, the status of music in the hierarchy of arts in the Analytic of the Sublime, and the Comment (Anmerkung) on music and laughter or wit. This work aknowledges Formalism as a theory of aesthetics of music which asserts that music pleases through nothing else than itself, i. e. neither through a content nor through expressed emotions. This thesis roots in On The Musically Beautiful by Eduard Hanslick in 1854. Hence we must assume that something like a musically beautiful exists, that this work endeavours to find as a trace in the texts of the kantian aesthetics. We establish, therefore, that these texts allow us to characterize the peculiarity of music by giving a formal thought of the sound, a formalist theory of expression and a physiological philosophy of music. This thesis, on its whole, starts with the question of the sound, and developps it, especially through the work of Johann Friedrich Herbart. His ambition is to define scientifically the musical thought (musikalisches Denken) by means of his sychology and metaphysics – too little known –. Hence, we propose an insight and a translation of one short opus. Herbart being constantly discussing with Kant, and anslick noticing the formalist thought of Herbart on music, a genuine and conceptual connection can so be revealed between these authors. Therefore the qualities of the sound may be defined, and, thereby, the qualities of the cornerstone of the formalist aesthetics, namely, the musically beautiful.