Imagine what would happen if pilots were to navigate, not by fixed reference points, but by beacons that moved about unpredictably and sometimes disappeared altogether! Disasters like the one at Mount Erebus would undoubtedly be common.
अर्थात, व्यक्‍तिपरत्वे व संस्कृतीपरत्वे नैतिक आदर्श देखील बदलू शकतात हा प्रचलित दृष्टिकोन.