The radical remedy lies in the mortification of the four great natural passions, joy, hope, fear, and grief. You must seek to deprive these of every satisfaction and leave them as it were in darkness and the void.
 William James, The Varieties of Religious Experience (1902). copy citation

Context

“You take pleasure in seeing objects which do not raise your mind to God: refuse yourself this pleasure, and turn away your eyes. The same with conversations and all other things. Act similarly, so far as you are able, with all the operations of the senses, striving to make yourself free from their yokes.
The radical remedy lies in the mortification of the four great natural passions, joy, hope, fear, and grief. You must seek to deprive these of every satisfaction and leave them as it were in darkness and the void. Let your soul therefore turn always:
“ Not to what is most easy, but to what is hardest;
“ Not to what tastes best, but to what is most distasteful;
“ Not to what most pleases, but to what disgusts;
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