“All That’s Known” is our first introduction to Melchior Gabor, a radical atheist who wishes to go against the ignorant information and rules he was taught in school and at church.

The song is sung during a Latin lesson after his friend, Moritz Stiefel, is reprimanded in class. Melchior attempts to justify Moritz' “error” as another interpretation to the situation and show that he was correct, in just another way. Herr Sonnenstitch, the professor, refuses to acknowledge Melchior’s insightful understanding of the verse and teacher hits Melchior when he refuses to compromise. Melchior then sings about the injustice he sees at school and vows to make everyone “know” someday.