What is Ressentiment for Nietzsche? Explain how this concept is central to his Genealogy of morals.

What is Ressentiment for Nietzsche? Explain how this concept is central to his Genealogy of morals.
Write a six page double spaced paper using textual evidence on the following topic. You need to reference a minimum of three sources other than the text

The text: On the Genealogy of Morality, Friedrich Nietzsche.

Chapters 10, 11 and 12, in Essay I, talk about Ressentiment if that can help.