The entire history of humanity is marked by a single inexorable movement - from animal instinct toward rational thought, from inborn behavior toward acquired knowledge. A half-grown panther abandoned in the wilderness will grow up to be a perfectly normal panther. But a half-grown child similarly abandoned will grow up into an unrecognizable savage, unfit for normal society. Yet there are those who insist the opposite: that we are creatures of instinct, like wolves.
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