As you'll learn when you read The Underground History of American Education the new purpose of schooling—to serve business and government—could only be achieved efficiently by isolating children from the real world, with adults who themselves were isolated from the real world, and everyone in the confinement isolated from one another.
Only then could the necessary training in boredom and bewilderment begin. Such training is necessary to produce dependable consumers and dependent citizens who would always look for a teacher to tell them what to do in later life, even if that teacher was an ad man or television anchor.
The rationale, history, and dynamics of "Fourth Purpose" school procedure are carefully examined in The Underground History of American Education.
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