"We know that the Zanj (blacks) are the least intelligent and the least discerning of mankind, and the least capable of understanding the consequences of actions."

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The bad economist sees only what immediately strikes the eye; the good economist also looks beyond. The bad economist sees only the direct consequences of a proposed course; the good economist looks also at the longer and indirect consequences. The bad economists sees only what the effect of a given policy has been or will be on one particular group; the good economist inquires also what the effect of the policy will be on all groups

— Henry Hazlitt