For if once a man indulges himself in murder, very soon he comes to think little of robbing; and from robbing he comes next to drinking and Sabbath-breaking, and from that to incivility and procrastination. Once begin upon this downward path, you never know where to stop. Many a man has dated his ruin from some murder or other that perhaps he thought little of the time.

thomas de quincey
Thomas De Quincey (1785-1859) English writer, essayist, literary critic
Essay (1839-11), “Second Paper on Murder Considered as One of the Fine Arts,” Blackwood’s Edinburgh Magazine, Vol. 46, No. 289
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