Clock Building, Not Time Telling

Imagine you met a remarkable person who could look at the sun or stars at any time of day or night and state the exact time and date: "It's April 23, 1401, 2:36AM and 12 seconds." This person would be an amazing time teller, and we'd probably revere that person for the ability to tell time. But wouldn't that person be even more amazing if, instead of telling the time, he or she built a clock that could tell the time forever, even after he or she was dead and gone?

- James C. Collins and Jerry I. Porras, Built to Last