"Who is a Jew?" An answer to this can only ever be an attempt at approximation. Nevertheless, in light of the increasing external determination by the majority society, it is vital for Jews to self-determine what and who they want to be, writes the author Gunda Trepp. Drawing on the Torah and Talmud as well as the positions of Jewish philosophers, she engages with current issues essential to the question of identity, such as conversion, patrilineal descent, and Zionism. She passionately advocates for a reorientation towards the revolutionary ideas of religious law. Halacha, with its monotheistic social ethics, has guided the Jewish people for millennia and placed them at the forefront of the fight for human rights and social justice. Can there still be a radical Jewish thought and action if this reference is permanently lost? Are Jews still Jews then? Continuously questioning her own insights, the author reflects in essays on the power of definition.