Medieval scholars linked celestial occurrences, such as Halley’s comet, to events at home, such as the arrival of William the Conqueror in England.
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The Catholic Church practice of granting indulgences, criticized by Martin Luther in the 16th century, still exists, as part of the doctrine – but in a different form.
For millennia, theologians taught that the sole purpose of sex was reproductive. Now, almost everyone agrees that sex has many purposes – and benefits.
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