French philosopher Félix Ravaisson (1813-1900) is one of the most influential sources of inspiration of the 20th-century philosophy, who is yet undervalued in our philosophical context. His seminal philosophical essay, Of Habit (De l'habitude, 1838), is based on Aristotle as well as on french spiritualists (Maine de Biran) and naturalists of the turn of the 19th century.
He analyses habit in the context of general philosophy of nature and in the context of philosophy of spirit. The phenomenon of habit points out the ontological unity of nature and spirit.
Ravaisson's treatise of habit was pivotal in the development of French thought and has had a significant influence on key thinkers such as Proust, Bergson, Heidegger, Ricoeur, Merleau-Ponty, Derrida, and Deleuze.