That is why man can also never understand himself: For he is himself a — Otto Weininger

"The highest expression of all morality is: Be!"

"As the mental endowment of a man varies with the organisation of his accumulated experiences, the better endowed he is, the more readily will he be able to remember his whole past, everything that he has ever thought or heard, seen or done, perceived or felt, the more completely in fact will he be able to reproduce his whole life. Universal remembrance of all its experiences, therefore, is the surest, most general, and most easily proved mark of a genius."

"A man is himself important precisely in proportion that all things seem important to him."

"There are men who are willing to marry a woman they do not care about merely because she is admired by other men. Such a relation exists between many men and their thoughts."

"In order to depict a man one must understand him, and to understand him one must be like him; in order to portray his psychological activities one must be able to reproduce them in oneself. To understand a man one must have his nature in oneself."

"People should also not want to determine themselves causally in such a way: I will now … become good once and for all, and do good by nature, because I could not then do anything else. For through this one denies the freedom which can in each moment negate all the past. … One makes himself into an object when one establishes causality in that way; for a morality to which I have been compelled is already not a morality."