What? You say that full energy given to those sixteen hours will lessen the value of the business eight? Not so. On the contrary, it will assuredly increase the value of the business eight. One of the chief things which my typical man has to learn is that the mental faculties are capable of a continuous hard activity; they do not tire like an arm or a leg. All they want is change-not rest, except in sleep.
( Cal Newport )
[ Deep Work: Rules for Focused ]
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