Martin Heidegger and his controversy.
Martin Heidegger (1889-1976), author of Being and Time (1927), is one of the most influential philosophers of the past century, however there is a controversy regarding his choice to remain in Germany while the majority of his colleagues emigrated to the USA or to other countries because they were Jews, or persecuted by Nazis for their ideas.
How could a man like Heidegger accept Nazism? He answered that he believed, like many others, that Hitler and Nazism would have started a new phase for Germany. Besides, Nazism appeared to him the only protection of the Da-sein (existence) from the Communist menace.
Thus Heidegger joined Nazism because he thought it would have protected the community, the projects and the language of Germany. However, after the war Heidegger, retracing his steps, defined Nazism as the expression of the Nihilism of the world-wide technical civilisation that made nothing.

Hannah Arendt and the Banality of Evil.
Hannah Arendt (1906-1975) is a German political philosopher, coming from a Jewish family; in 1941 she escaped to the United States where she taught and wrote until she died in 1975.
She wrote a book dedicated to some ethical questions involved in the extermination of Jews: Eichmann in Jerusalem. A Report on the Banality of Evil. (1963).
Otto Adolf Eichmann was a German Nazi, member of the SS, entrusted with the deportation of Jews from the Ghettos in the main European cities to the extermination camps. In 1960 Mossad, the Israeli intelligence agency, captured him in Argentina and took him to Israel to be judged by an Israeli court for 15 charges, including crimes against humanity and war crimes; he was found guilty and executed by hanging in 1962.
For the author, the expression "banality of evil" synthesizes the attitude of Eichmann and of many criminals like him: Eichmann and his colleagues belonging to the SS were just ordinary people who considered their actions simply normal in that context, because they were obeying the orders as if they were moral imperatives.

Hans Jonas: the Shoah and God.
Hans Jonas (1903-1993) is a Jewish philosopher who is very well learned in rabbinic studies and one of his main books is The Concept of God after Auschwitz. A Jewish Voice (1984).
Assuming that the Jews are the chosen people who remained faithful to the one God, the Shoah struck innocent Jews. Although God's attributes should be goodness, comprehensibility and omnipotence, Hans Jonas doubts: the coexistence of omnipotence and goodness makes God absolutely incomprehensible, especially if we consider the Shoah.
To describe the creation of the world and of man Jonas uses the expression "contraction of God", in the sense that God created the world by reducing its power and presence, thus allowing the world to evolve freely. Men and women are free and responsible because God is not omnipotent.

Emmanuel Lévinas: the Imperialism of the Same and the Transcendence of the Other.
Emmanuel Lévinas (1905-1995) is a phenomenologist and moral thinker. Born in Lithuania, he spent a few years in Germany and was then imprisoned during the Second World War.
In his book Totality and Infinity (1961), Lévinas interprets the Shoah as the ontological violence of traditional philosophy.
The clear distinction between the concept of the Other and the Self has led to the imperialism of the latter over the former. This ethical relationship with the Other is entrusted to God because, biblically speaking. He is the invisible and the objective par excellence. God, in the encounter between the two entities, makes men responsible for one another.