Full Idea
It has gradually become clear to me what every great philosophy has hitherto been: a confession on the part of its author, and a kind of involuntary and unconscious memoir, ...with moral intentions being the real germ of its life.
Gist of Idea
Great philosophies are confessions by the author, growing out of moral intentions
Source
Friedrich Nietzsche (Beyond Good and Evil [1886], §006)
Book Reference
Nietzsche,Friedrich: 'Beyond Good and Evil', ed/tr. Hollingdale,R.J. [Penguin 1973], p.19
A Reaction
This attitude is what places Nietzsche as the parent of post-modernism, and is the reason why most 'continental' philosophers seem to have given up the attempt to simply reason about life. It is anti-Enlightenment, and it is wicked.