by mk

  It comes from a story about a man who joined a friend down at the docks.
  They were working in a fish market. Their job was to "trade" fish.

  All day long the price would change dramatically, the action was fast and furious.
  Buying and selling, selling, buying, etc. Making and losing large sums of money.

  Finally the day ended. The man was hungry so he opened one of the fish
  containers he had been trading and took a bite. "Hey", he exclaimed, "these fish
  are rotten!".

  "Those aren't eating sardines", his friend explained, "they are TRADING sardines".

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