He wrote more than ten books and was a master of German prose. One can distinguish several phases or approaches in his books, all of which are well-written but some of which are obscure nevertheless. In any case, he was aristocratic, pessimistic and mostly materialistic, though his attitude to science and rationality differed considerably in his different phases and books.

He has been widely influential in artistic circles, if only because he brilliantly expresses a young man's cynicism about the world in combination with personal high aspirations, and also as one of the main inspirators of Adolf Hitler and national socialism, though it is very probable that Nietzsche would have despised Hitler, and it is certain that Nietzsche was neither an antisemite nor a German nationalist nor a socialist in any sense.

A sympathetic reading of him tends to see him as an aristocratic individualist of great gifts, unfortunately side-tracked and finally upset by serious bad health; a less sympathetic reading sees him as a disturbed personality of great linguistic gifts who through his cravings for personal superiority, aristocracy and a master-race laid, albeit unwittingly, the foundations for fascism and national socialism.

What is certain in any case, however one tries to understand him, is that almost all of his followers have not understood him, but only used such of his brilliancies as fitted their own ends.

One of his phrases and ideals that appealed to Hitler and national socialists was the notion of a Herrenmoral: A morality for leaders of the master race, of whom Nietzsche liked to think that the world exists mostly for their purposes, and that, being naturally superior, they had, thereby and therefore, the right, and possibly the duty, to subvert and use everybody else for their - superior, enlightened - ends. (It should be clear that, however one thinks about the distribution of talents, this Nietzschean opinion also seems a prime example of Adlerian psychological compensation for weakness and inferiority, and that it was this aspect that, unwittingly, grabbed Hitler and other national socialists, who strongly craved superiority.)

The general problem with Nietzsche as a philosopher is that he was very good at writing philosophical and psychological aphorisms, but no good at all at writing systematic rational philosophical expositions of his ideas.

Another problem is that his works have not been fully published (and he became insane aged 44) and that his sister has falsified some of these to satisfy her own antisemitism. His last unpublished work, "The Will to Power", has been edited and published by Schlechta, but is supposed to be incomplete.

If Seneca was right that there is no genius without a tincture of madness, Nietzsche is a good example of a mad philosophical genius, whose genius was mostly linguistic: A great gift for spectacular phrasing, but a far lesser gift for systematic rational thinking and exposition.