Thus May You Feel Your Pulse

From the journals of
Henry David Thoreau:

February 25, 1859/

Measure your health by your sympathy with morning and spring. If there is no response in you to the awakening of nature,--if the prospect of an early morning walk does not banish sleep, if the warble of the first bluebird does not thrill you,--know that the morning and the spring of your life are past. Thus may you feel your pulse.