I have found, for example, that if I have to write upon some rather difficult topic the best plan is to think about it with very great intensity - the greatest intensity of which I am capable - for a few hours or days, and at the end of that time give orders, so to speak, that the work is to proceed underground. After some months I return consciously to the topic and find that the work has been done.
Source:The Conquest of Happiness, 1930, chap. 5.
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