An ideal clock is a clock (i.e., recurrent process) that makes the most other recurrent processes periodic.

— Wikipedia on Clock

The ideal clock itself is a meta-clock — a property of a set of clocks.

— Me@2015-04-16 9:35 AM

If you compare the accuracies of two clocks (A and B) by comparing each of them with a third clock (C), then I can ask, “How can you know that C is more accurate than both A and B?”

By defining the ideal clock as a meta-clock, we avoid infinite regress.

— Me@2015-04-27 11:36:59 AM

2015.04.29 Wednesday (c) All rights reserved by ACHK