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  "url": "https://www.leafyquotes.com/colin-wilson/the-mammoth-encyclopedia-of-the-unsolved/the-progress-of-human",
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  "slug": "the-progress-of-human",
  "text": "The progress of human knowledge depends on maintaining that touch of scepticism even about the most \"unquestionable\" truths. A century ago, Darwin's theory of evolution by natural selection was regarded as scientifically unshakeable; today, most biologists have their reservations about it. Fifty years ago, Freud's sexual theory of neurosis was accepted by most psychiatrists; today, it is widely recognized that his methods were highly questionable. At the turn of this century, a scientist who questioned Newton's theory of gravity would have been regarded as insane; twenty years later, it had been supplanted by Einstein's theory, although, significantly, few people actually understood it. It seems perfectly conceivable that our descendants of the twenty-second century will wonder how any of us could have been stupid enough to have been taken in by Darwin, Freud or Einstein.",
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  "author": {
    "name": "Colin Wilson",
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    "title": "The Mammoth Encyclopedia of the Unsolved",
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  "page": 4,
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  "topics": [
    {
      "name": "science",
      "slug": "science",
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      "name": "doubt",
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  "added_at": "2026-09-25T22:50:23",
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