LitCharts assigns a color and icon to each theme in Thus Spoke Zarathustra, which you can use to track the themes throughout the work.
Rethinking Morality
The Superman and the Will to Power
Death of God and Christianity
Eternal Recurrence
Summary
Analysis
At night, the “unquenchable” speaks out. Zarathustra constantly gives and doesn’t know the joy of receiving; he has an unsated hunger and, like all givers, is alone. Zarathustra laments the necessity of being light; he yearns to be night instead.
Zarathustra sings about the pain and longing in solitude. The higher individual constantly pours out to others by means of the inexhaustible will to power and therefore cannot be emotionally or spiritually filled. This is a lonely life.