To know anything about oneself one must know all about others. There must be no mood with which one cannot sympathise, no dead mode of life that one cannot make alive.
 Oscar Wilde, Intentions (1891). copy citation

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Author Oscar Wilde
Source Intentions
Topic mood life
Date 1891
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/887/887-h/887-h.htm

Context

“For he to whom the present is the only thing that is present, knows nothing of the age in which he lives. To realise the nineteenth century, one must realise every century that has preceded it and that has contributed to its making. To know anything about oneself one must know all about others. There must be no mood with which one cannot sympathise, no dead mode of life that one cannot make alive. Is this impossible? I think not. By revealing to us the absolute mechanism of all action, and so freeing us from the self-imposed and trammelling burden of moral responsibility, the scientific principle of Heredity has become, as it were, the warrant for the contemplative life.” source