The Birth of Tragedy (1872)
On Truth and Lie in an Extramoral Sense (1873)
Untimely Meditations (1873–6)
Human, All Too Human (1878)
The Wanderer and his Shadow (1880)
The Dawn/Daybreak (1881)
The Joyous Science (1882, 1887)
Thus Spoke Zarathustra (1883–5)
Beyond Good and Evil (1886)
On the Genealogy of Morals (1887)
The Case of Wagner (1888)
Twilight of the Idols (1888)
The Antichrist (1888)
Ecce Homo (1888)
Nietzsche contra Wagner (1888)
The Will to Power (1901)
Allan Bloom’s The Closing of the American Mind would make a great introduction to Nietzsche and his importance, besides being an extraordinarily clearly-written account of Where-we-are-now and How-we-got-here, (via Hobbes, Locke, Kant, Rousseau, Nietzsche, Weber, Freud etc.) politically, culturally, intellectually, artistically etc.
H.L. Mencken, The Philosophy of Friedrich Nietzsche (1907) – read online – The first book on Nietzsche written in English.
George Santayana, Egotism in German Philosophy, ch. 11-13 – read online
Walter Kaufmann, Nietzsche: Philosopher, Psychologist, Antichrist
Richard Schacht, Nietzsche
Alexander Nehemas, Nietzsche: Life as Literature
Jonathan Glover, Humanity: A Moral History of the Twentieth Century, 1999. Looks at the dark side of Nietzsche, which books such as the next seem oblivious to.
The Cambridge Companion to Nietzsche
++++All that was true in his teaching was this: that if a man looks fine on a horse it is so far irrelevant to tell him that he would be more economical on a donkey or more humane on a tricycle. In other words, the mere achievement of dignity, beauty, or triumph is strictly to be called a good thing. I do not know if Nietzsche ever used the illustration; but it seems to me that all that is creditable or sound in Nietzsche could be stated in the derivation of one word, the word “valour.” Valour means valeur; it means a value; courage is itself a solid good; it is an ultimate virtue; valour is in itself valid. In so far as he maintained this Nietzsche was only taking part in that great Protestant game of see-saw which has been the amusement of northern Europe since the sixteenth century. Nietzsche imagined he was rebelling against ancient morality; as a matter of fact he was only rebelling against recent morality, against the half-baked impudence of the utilitarians and the materialists. He thought he was rebelling against Christianity; curiously enough he was rebelling solely against the special enemies of Christianity, against Herbert Spencer and Mr. Edward Clodd. Historic Christianity has always believed in the valour of St. Michael riding in front of the Church Militant; and in an ultimate and absolute pleasure, not indirect or utilitarian, the intoxication of the spirit, the wine of the blood of God.
++++There are indeed doctrines of Nietzsche that are not Christian, but then, by an entertaining coincidence, they are also not true. His hatred of pity is not Christian, but that was not his doctrine but his disease. Invalids are often hard on invalids. And there is another doctrine of his that is not Christianity, and also (by the same laughable accident) not common-sense; and it is a most pathetic circumstance that this was the one doctrine which caught the eye of Shaw and captured him. He was not influenced at all by the morbid attack on mercy. It would require more than ten thousand mad Polish professors to make Bernard Shaw anything but a generous and compassionate man. But it is certainly a nuisance that the one Nietzsche doctrine which attracted him was not the one Nietzsche doctrine that is human and rectifying. Nietzsche might really have done some good if he had taught Bernard Shaw to draw the sword, to drink wine, or even to dance. But he only succeeded in putting into his head a new superstition, which bids fair to be the chief superstition of the dark ages which are possibly in front of us—I mean the superstition of what is called the Superman.
++++In one of his least convincing phrases, Nietzsche had said that just as the ape ultimately produced the man, so should we ultimately produce something higher than the man. The immediate answer, of course, is sufficiently obvious: the ape did not worry about the man, so why should we worry about the Superman? If the Superman will come by natural selection, may we leave it to natural selection? If the Superman will come by human selection, what sort of Superman are we to select? If he is simply to be more just, more brave, or more merciful, then Zarathustra sinks into a Sunday-school teacher; the only way we can work for it is to be more just, more brave, and more merciful; sensible advice, but hardly startling. If he is to be anything else than this, why should we desire him, or what else are we to desire? These questions have been many times asked of the Nietzscheites, and none of the Nietzscheites have even attempted to answer them. – G.K. Chesterton, George Bernard Shaw
Other vague modern people take refuge in material metaphors; in fact, this is the chief mark of vague modern people. Not daring to define their doctrine of what is good, they use physical figures of speech without stint or shame, and, what is worst of all, seem to think these cheap analogies are exquisitely spiritual and superior to the old morality. Thus they think it intellectual to talk about things being “high.” It is at least the reverse of intellectual; it is a mere phrase from a steeple or a weathercock. “Tommy was a good boy” is a pure philosophical statement, worthy of Plato or Aquinas. “Tommy lived the higher life” is a gross metaphor from a ten-foot rule.
++++This, incidentally, is almost the whole weakness of Nietzsche, whom some are representing as a bold and strong thinker. No one will deny that he was a poetical and suggestive thinker; but he was quite the reverse of strong. He was not at all bold. He never put his own meaning before himself in bald abstract words: as did Aristotle and Calvin, and even Karl Marx, the hard, fearless men of thought. Nietzsche always escaped a question by a physical metaphor, like a cheery minor poet. He said, “beyond good and evil,” because he had not the courage to say, “more good than good and evil,” or, “more evil than good and evil.” Had he faced his thought without metaphors, he would have seen that it was nonsense. So, when he describes his hero, he does not dare to say, “the purer man,” or “the happier man,” or “the sadder man,” for all these are ideas; and ideas are alarming. He says “the upper man,” or “over man,” a physical metaphor from acrobats or alpine climbers. Nietzsche is truly a very timid thinker. He does not really know in the least what sort of man he wants evolution to produce. And if he does not know, certainly the ordinary evolutionists, who talk about things being “higher,” do not know either.
– GK Chesterton, Orthodoxy