Truth is our element of life, yet if a man fasten his attention on single aspect of truth, and apply himself to that alone for a long time, the truth becomes distorted and not itself, but falsehood; herein reassembling the air, which is our natural element, and the breath of our nostrils, but if a stream of the same be directed on the body for a time, it causes cold, fever, and even death. How wearisome the grammarian, the phrenologist, the political or religious fanatic, or indeed any obsessed mortal whose balance is lost by the exaggeration of a single topic. It is incipient insanity. Every thought is a prison also. I cannot see what you see, because I am caught up by a strong wind, and blown so far in one direction that I am out of the hoop of your horizon.
Source: Nature and Other Essays. Dover: 2009, pg. 77