The insignificance and tenacity of the light of reason in the boundless and crazy universe.
The double-edged sword of knowledge: both a source of power and a source of madness and destruction.
In a desperate situation, survival, responsibility and the glory of humanity. Questioning of "gods" and "faith" (the gods worshiped by the church may simply be more powerful alien entities or false gods).
The fierce collision between modernity and the medieval worldview, scientific thinking and mysticism.