Kierkegaard, Søren.

p. 281, in “The Rotation Method” section (p. 279-96): Starting from a principle is affirmed by people of experience to be a very reasonable procedure; I am willing to humor them, and so begin with the principle that all men are bores. Surely no one will prove himself so great a bore as to contradict me in this. The principle possesses the quality of being in the highest degree repellent, an essential requirement in the case of negative principles, which are in the last analysis the principles of all motion. It is not merely repellent, but infinitely forbidding; and whoever has this principle back of him cannot but receive an infinite impetus forward, to help him make new discoveries. For; if my principle is true, one need only consider how ruinous boredom is for humanity, and by properly adjusting the intensity of one’s concentration upon this fundamental truth, attain any desired degree of momentum. Should one wish to attain the maximum momentum, even to the point of almost endangering the driving power, one need only say to oneself: Boredom is the root of all evil. Strange that boredom, in itself so staid and stolid, should have such power to set in motion. The influence it exerts is altogether magical, except it is not the influence of attraction, but of repulsion.