'Why Don't We Learn From History' by B.H. Liddell Hart

"It is strange how people assume that no training is needed in the pursuit of truth. It is stranger still that this assumption is often manifest in the very man who talks of the difficulty of determining what is true. We should recognize that for this pursuit anyone requires at least as much care and training as a boxer for a fight or a runner for a marathon. He has to learn how to detach his thinking from every desire and interest, from every sympathy and antipathy; like ridding oneself of superfluous tissue, the "tissue" of untruth which all human beings tend to accumulate for their own comfort and protection. And he must keep fit, to become fitter. In other words, he must be true to the light he has seen.⁣
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He may realize that the world is a jungle. But if he has seen that it could be better for anyone if the simple principles of decency and kindliness were generally applied, then he must in honesty try to practice these consistently and to live, personally, as if they were general. In other words, he must follow the light he has seen."⁣⁣
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From 'Why Don't We Learn From History' by B.H. Liddell Hart