Friedrich Nietzsche's reaction against the pessimistic philosophy…

Friedrich Nietzsche's reaction against the pessimistic philosophy of Wagner and Schopenhauer becomes evident with the publication in 1878 of Human, All Too Human (a book of aphorisms on subjects ranging from metaphysics to morality and from religion to the sexes), as well as the influence of Afrikan Spir's Denken und Wirklichkeit (Thought and Reality).

Nietzsche's friendship with Paul Deussen and Erwin Rohde cools as well.

In 1879, after a significant decline in health, Nietzsche has to resign his position at Basel. (Various disruptive illnesses have plagued him since his childhood, including moments of shortsightedness that leave him nearly blind, migraine headaches, and violent indigestion. The 1868 riding accident and diseases in 1870 may have aggravated these persistent conditions, which continue to affect him through his years at Basel, forcing him to take longer and longer holidays until regular work became impractical.)