This isn't just going to be a book review, since I have Library Thing now. Instead, this is my interpretation of his philosophy and how it relates to my own philosophy. Still though, it is eloquent, profound, and enlightening. I would strongly recommend reading it—my writing style won't be close to emulating his. Be prepared to have your vocabulary tested though.

Ontology

The first key idea in how Nietzsche thinks is how he thinks of actions. To him, there is no such thing as an "independent" will. There are only forces. For example, to him, a hawk can't be separated from hawk things, such as hunting prey. So even though the hawk is killing, this action isn't moral or immoral. It is merely their nature. So the hawk only does what it does. As another example, he looks at the sentence "Lightning flashes." It would be absurd to think of lightning as something that had the choice to flash. This idea is similar to my idea that free-will as the self is immutable. So to him, why morality seems to exist is merely a grammatical thing.

Morality

His account of morality begins with a narrative of how morality was invented. The strong, the powerful, the rulers of society saw that it was beneficial for them to create the idea of the "good" so that they could call themselves good and convince the subjected that the "good" was in their interests. This way, they can maintain power better. His evidence for this was in language, in how certain words have been associated with class and moral goodness/normative statements (read it if you want more details). In this moral system, it is greed by the ruling that is good. This is master morality.

This contrasts with what he calls "slave" morality: the morality created by the subjected. First off, religion is what allowed slave morality to exist. The priest with his ascetic ideals inspired reverence from the subjected and convinced them to work together, to put their will to powers together and create something historic. By doing so, they reverse the individual man's destructive nature inwards and open a world of complexity, spawning literature and art. The basis of slave morality is a reversal of who is good. It is based on self-control, an inversion of the self-interested, gobbling yes in the master morality. Now, instead of the good being the powerful, the good is something more democratic, and their "masters" are forever condemned for their sins.

I think this description of morality makes a lot of sense. Of course, as man created civilizations and had language, those in power would want to create a system that promoted it. This is the moral system of those who believe the legal system to be moral. And looking at religion, it really does make sense as a way of organizing the masses. I don't want to go into a whole ton of detail, but Nietzsche also argues that man had an instinct to destroy (he examines how punishment and justice have evolved). This account of religion turning this destructive instinct on himself accounts so well for how we hate ourselves and our self-image. This accounts for how we get so torn up about our own failings and how we blame ourselves so often for things out of our control. This view also explains how religion drives the masses to greatness: by justifying pain and sacrifice as virtues that will eventually be repaid in heaven, he gets the "slaves" of society to push through the pain, to even seek it out!

"that, as I said, is the benefit of active forgetfulness, like a doorkeeper or guardian of mental order, rest and etiquette ... there could be no happiness, no cheerfullness, no hope, no pride, no present without forgetfullness"

—Nietzsche

In this way, Nietzsche leads to a quite modern view of the mind. In order to unleash our full potential, Nietzsche believes that we need to free ourselves from the chains of morality and religion that hold us back; these chains only serve to cause us to hate ourselves and dwell on our past for too long, instead of having a strong "digestive system" that will naturally process our emotions. This just sounds like therapy. So the great people are those with a healthy mind.

Human Nature

This naturally leads to a nice categorization of mankind.

• The "sick", i.e. the ones stuck in a morality system
• The priests, i.e. those who have the strength to follow through on an ascetic ideal but still are stuck in a moral system and alleviate the symptoms of the disease of morality (notably not curing it)
• The great, i.e. those who can process their failings and overcome, those who have what it takes to sort of make history and achieve greatness (this term has become cringe lately, but they are the Übermensch)

But using the term "priest" here is a bit too suggestive of religion. They don't merely have to commit to religious ideals. Nietzsche talks a ton about science in the third essay, but the ideal is more like something one can identify as. E.g. committed scientists follow through on the ideal of truth. In this way, Nietzsche captures my thoughts on identity: that they often hold us back from being able to look at reality. This is deserving of its own post in the future.

In this book, Nietzsche builds the groundwork for perspectivism and postmodernism in how he sees the truth as something that doesn't objectively exist. Instead, we need multiple frameworks and perspectives to understand it. To him, entrenched in any analysis is the culture of the time. He also has some great stuff about the social contract and justice in this book, as well as some (imo dubious) remarks about promises. Overall, what a fantastic book and it is very short sitting at about 125 pages.

The stereotypes

Just a section here to address some stereotypes of Nietzsche. He isn't a nihilist. He is very, very much so an existentialist in how he questions and analyzes and tries to create meaning in our lives. He explicitly is doing this to combat the rise of nihilism in Europe. He despises the lethargy that nihilism promotes. He also isn't a Nazi, having literally said "I also dislike the latest speculators in idealism, the anti-Semites..." (Diethe translation, page 120). Admittedly, he is a bit sexist in this book, but it is more of a random word drop and also possibly due to saltiness from his love life (he proposed and was rejected 3 times). Also, in some places, it can be seen as him remarking on the image of women at that time. Although, it is entirely possible he is just sexist.