The term may originate from an English proverb that warns against selling the bear’s skin before one has caught the bear, which might describe a situation in which a speculator sells a stock with the assumption that it can be bought later at a lower price. An alternative origin may come from a 1709 issue of the United Kingdom’s satirical paper, The Tatler, which told a story about a noble gentleman who bought a bear, sight unseen, from another officer. The deal went bad, and it was said that someone who confers real value upon an imaginary thing is selling a bear. The different descriptions for bull and bear markets may also be derived from the fact that a bear attacks by coming down on its prey while a bull attacks its prey by thrusting its horns upward.
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