in Thoreau’s Journal:
Why need I travel to seek a site, and consult the points of the compass? My eyes are south windows, and out of these I command a southern prospect. The eye does the least drudgery of any of the senses. It oftenest escapes to a higher employment. The rest serve and escort and defend it. I attach some superiority, even priority, to this sense. It is the oldest servant in the soul’s household; it images what it imagines, it ideates what it idealizes. Through it idolatry crept in which is a kind of religion. If any joy or grief is to be expressed, the eye is the swift runner that carries the news. In circumspection, double, in fidelity, single, it serves truth always, and carries no false news….
How man serves this sense more than any other! When he builds a house, he does not forget to put a window in the wall. We see truth. We are children of light. Our destiny is dark. No other sense has so much to do with the future. The body of science will not be complete till every sense has thus ruled our thought and language and action in its turn.