Nietzsche took life sciences as a basis to build up some of his most important concepts such as ‘will to power’ or ‘force’. Accordingly, life sciences are important to understand Nietzsche’s philosophy in general. Nietzsche called naturalization (Vernatürlichug) of what is human the study of social phenomena through life science concepts. In this paper I will point out the elements composing this philosophical enterprise of ‘naturalization’ of the human. More explicitly, I will show that a certain turn in the notion of ‘organism’ explains Nietzsche’s understanding of the temporality of historical events.Nietzsche utiliza supuestos de las ciencias de la vida para construir conceptos fundamentales de su pensamiento tales como el de ‘voluntad ...