Time is still something we don't fundamentally understand. All we have is the instant when we do some kind of analysis in our heads of events and try to make a

Time is still something we don't fundamentally understand. All we have is the instant when we do some kind of analysis in our heads of events and try to make a decision about time as it relates to those events. "Time flies when you're having fun", but it also flies when you're working hard toward a deadline, and while sleeping! The title gets it right -- time "feels" slower because "time feels X" is as good as science gets right now.