More than a century and a half before our modern malady of confusing productivity with purposefulness and the urgent with the important, Thoreau wrote in an entry from the last day of March in 1842:
The really efficient laborer will be found not to crowd his day with work, but will saunter to his task surrounded by a wide halo of ease and leisure. There will be a wide margin for relaxation to his day. He is only earnest to secure the kernels of time, and does not exaggerate the value of the husk. Why should the hen set all day? She can lay but one egg, and besides she will not have picked up materials for a new one. Those who work much do not work hard.