Don’t loaf and invite inspiration; light out after it with a club, and if you don’t get it you will nonetheless get something that looks remarkably like it.

Jack London (1876-1916) American novelist

Essay (1903-03), “Getting into Print,” The Editor Magazine, Vol. 17, No. 3
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Often misquoted as "You can't wait for inspiration. You have to go after it with a club."

Reprinted in J. Reeve, Practical Authorship (1905).