Death and Time

Death is what makes time relevant. The measurement of time is merely counting down the seconds to our ends.

If no one died, ever, then we would be entirely unconcerned with the measurement of time. A second and a year would be, functionally, the same thing. There would be no rush to do anything, because we could always do it later. (I don't know if this would encourage procrastination or render it irrelevant) 

On the other hand, if only one person (lets say....ooh, me, pick me) was immortal, then I would care about time but priorities would be radically different. My personal agenda could be postponed, my concern about myself would be unbound by any deadline. But everyone around me would only be here for a (relatively) short time, so my primary concern would be spending time with people before they died.

So I think instead of living each day like it's our last, we should live each day like we will live forever. There's always time for ourselves, it's other people we should be concerned about.