Strauss, Leo.  "Note on the Plan of Beyond Good and Evil."  In Studies in Platonic Philosophy.  Chicago: U of Chicago Press, 1983.

Excerpt:

“[1] Beyond Good and Evil always seemed to me to be the most beautiful of Nietzsche’s books. This impression could be thought to be contradicted by his judgement, for he was inclined to believe that his Zarathustra is the most profound book that exists in German as well as the most perfect in regard to language. But “most beautiful” is not the same as “most profound” and even as “most perfect in regard to language”. To illustrate this partly by an example which is perhaps not too far-fetched, there seems to be general agreement to the effect that Plato’s Republic, his Phaedrus and his Banquet are his most beautiful writings without their being necessarily his most profound writings. Yet Plato makes no distinction among his writings in regard to profundity or beauty or perfection in regard to language; he is not concerned with Plato – with his “ipsissimosity” – and hence with Plato’s writings, but points away from himself whereas Nietzsche points most emphatically to himself, to “Mr. Nietzsche.” Now Nietzsche “personally” preferred, not Beyond Good and Evil but his Dawn of Morning and his Gay Science to all his other books precisely because these two books are his most personal” books (letter to Karl Knortz of June 21, 1888). As the very term “personal”, ultimately derivative from the Greek word for “face”, indicates, being “personal” has nothing to do with being “profound” or with being “perfect in regard to language”. “

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