Man has been reared by his errors: first he never saw himself other than imperfectly, second he attributed to himself imaginary qualities, third he felt himself in a false order of rank with animal and nature, fourth he continually invented new tables of values and for a time took each of them to be eternal and unconditional...If one deducts the effect of these four errors, one has also deducted away humanity, humaneness, and 'human dignity'.

J. In the following few days Nietzsche sent short writings—known as the Wahnbriefe ("Madness Letters")—to a number of friends (including Cosima Wagner and Jacob Burckhardt). Now with the new style of Zarathustra his work became even more alienating and the market received it only to the degree required by politeness.

Nietzsche's key ideas include the "death of God" the Übermensch the eternal recurrence the Apollonian and Dionysian dichotomy perspectivism and the will to power. His sister Elisabeth Förster-Nietzsche acted as curator and editor of Nietzsche's manuscripts during his illness. [citation needed].