Time Is Not What the Clock Says There is a particular cruelty to clocks. Not in what they measure, but in what they imply — that time moves at a single, agreed-upon rate. That the hour before a diagnosis lasts as long as the hour before a holiday. That grief and joy occupy identical units of duration. Anyone who has sat with loss, or with great beauty, knows this to be a quiet lie. The clock, of course, doesn't care. Physics, for most of its history, didn't either. Time was a