One summer more than ten years ago, when I taught at Princeton, a large spider appeared in the urinal of the men’s room in 1879 Hall, a building that houses the Philosophy Department. When the urinal wasn’t in use, he would perch on the metal drain at its base, and when it was, he would try to scramble out of the way, sometimes managing to climb an inch or two up the porcelain wall at a point that wasn’t too wet. But sometimes he was caught, tumbled and drenched by the flushing torrent. He didn’t seem to like it, and always got out of the way if he could. But it was a floor-length urinal with a sunken base and a smooth overhanging lip: he was below flöor level and couldn’t get out.
Somehow he survived, presumably feeding on tiny insects attracted to the site, and was still there when the fall term began. The urinal must have been used more than a hundred times a day, and always it was the same desperate scramble to get out of the way. His life seemed miserable and exhausting.
Gradually our encounters began to oppress me. Of course it might be his natural habitat, but because he was trapped by the smooth porcelain overhang, there was no way for him to get out even if he wanted to, and no way to tell whether he wanted to. None of the other regulars did anything to alter the situation, but as the months wore on and fall turned to winter I arrived with much uncertainty and hesitation at the decision to liberate him.
Thomas Nagel, The View from Nowhere, New York, 1986, pp. 208-209