1)The actual origins of these expressions are unclear. Here are two of the most frequent explanations given:
The terms "bear" and "bull" are thought to derive from the way in which each animal attacks its opponents. That is, a bull will thrust its horns up into the air, while a bear will swipe down. These actions were then related metaphorically to the movement of a market: if the trend was up, it was considered a bull market; if the trend was down, it was a bear market.
2)Historically, the middlemen in the sale of bearskins would sell skins they had yet to receive. As such, they would speculate on the future purchase price of these skins from the trappers, hoping they would drop. The trappers would profit from a spread - the difference between the cost price and the selling price. These middlemen became known as "bears", short for bearskin jobbers, and the term stuck for describing a downturn in the market. Conversely, because bears and bulls were widely considered to be opposites due to the once-popular blood sport of bull-and-bear fights, the term bull stands as the opposite of bears.
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