It is truly amazing the number of supposedly sentient beings in the universe that don't seem to be able to "find the time." Given that there is just so much of the stuff flowing around us, carrying along birthdays and anniversaries and absolutely-positively-the-last-chance-get-it-done-or- you're-fireds, you'd think that people would be finding it coming out their ears (this being the orifice of choice of over 90% of sentient beings when asked what orifice their excess possessions flow out of). But no.
Of course, when I say people, I don't mean everyone. Wowbagger the Infinitely Prolonged, that big dumb jerk, is profoundly aware of time. He was one of the first people to point out the unusual fact that time seems to "pile up" on Sunday afternoons, leaving many people crushed by the weight of it. It is this peculiar weight that makes people feel particularly listless all that afternoon, and totally wiped out the next morning. In view of this, many of the more advanced societies have made Monday the day of rest, and given Sunday over to activities that consume vast amounts of time, such as committee meetings and governmental emergency response activities. (Of course, the even more advanced societies have eliminated both committees and governments, and get rid of the excess time by exporting it to planets with temporal deficits. The most advanced societies have also eliminated economics, and deal with the excess time by shifting it back to Saturday night, where it's put to much better use.)
Some philosophers have theorized that this tendency not to notice time is rooted in the evolutionary principle of survival of the fittest. Given the huge amounts of time that there are, people who noticed time would be too busy noticing it to notice other things, such as that succulent apple-pie tree in the near distance, or that even more succulent member of the appropriate sex giving them that come-hither look. Such people never get a chance to reproduce, and so don't pass on their genes. The result of all this is that we end up with species that never fail to notice apple pies or members of the appropriate sex, which explains why so many people are run down by lorries outside of nudist bakeries.
Of course, if there were anything to the theory of evolution, there wouldn't be any philosophers around to propound this other theory, so the whole thing's a load of bunk, anyway.