Here are some of the most essential ideas in Nietzsche's philosophy. Nietzsche was not a programmatic thinker, and his ideas often have something more like the quality of poetic insights than components of a philosophical system. His thoughts, therefore, sometimes seem dissonant or contradict one another.
Eternal Recurrence and Amor Fati
These two ideas should be placed together. Eternal Recurrence means that, since time is infinite, and the number of events is finite, every event will recur over and over again. In The Gay Science, Nietzsche asks the reader to imagine that a demon tells us we must live the same life over and over again forever. Most people would regard this as a hideous punishment. If, however, we embrace life completely, we would hail the demon as a god and be joyful at the news. This would constitute Amor Fati, the love of fate.
The German word "Ubermensch" is notoriously difficult to translate and is generally rendered as "Superman" or "Overman." Perhaps the most accurate conception of Nietzsche's meaning, however, is conveyed by "Beyond-man." In Thus Spake Zarathustra, Nietzsche says that humanity is something to be transcended, as we have transcended the apes. When we look at a human and an ape, we do not think that the human is morally better but primarily that the human is more powerful and wiser: a higher type of being. This is how the beyond-man will appear when compared with petty, childish, foolish humanity.
Master Morality and Slave Morality
In his book On the Genealogy of Morality, Nietzsche argues that there are two types of morality: for masters and for slaves. The master morality emphasizes pride and independence. It is beyond good and evil and is scornful of mediocrity. The slave morality values kindness and humility. Nietzsche is critical of Christianity for promoting the slave morality and giving rise to democracy, which encourages the same values.
God is Dead and Nihilism
In Thus Spake Zarathustra and other works, Nietzsche says that God is dead (in The Gay Science, he adds that we have killed him). By this, he means that Enlightenment philosophy and an increase in scientific knowledge have made it impossible to believe in the God of the Bible. We now base all our morality on something we know is not true. Nihilism, the complete absence of values, is the price we pay for having believed in a false religion for almost two thousand years and for continuing to live according to its moral system.