Etty Hillesum was a militant advocate for the humanum, a collective name for human, humankind, or humanity. As such, she opposed hatred, anger, and barbarity. She considered that even the German enemy should not be treated wrongfully:

Humanism had three prominent spokesmen in the 20th century: Martin Heidegger (1889-1976), Jean-Paul Sartre (1905-1980), and Emmanuel Mounier (1905-1950).

Heidegger's foundation was Seinsvergessenheit and he brought the question of “Being” to the forefront as the creative force in the universe. On the wave of Being, humans can liberate themselves from the dictatorship of the anonymous “Man”, the masses. Heidegger's humanism is a relentless mission from “Man” to “human” or from homo barbarus to homo humanus. All things considered, Heidegger formulated anti-humanism as totally different from the human; a complete makeover of the human person, not just a choice among choices. Being in its truest form is liberated from inhumanity and barbarity and emancipated to a full humanity.

Sartre's humanism, on the other hand, was based upon the absolute and principled freedom of the rational human, the thinking subject, summarized in his short dictum, “existence precedes essence”. Human beings construct themselves and their existence by freely developing themselves through selfactualisation or self-realization.