I must admit, I was almost convinced by your retort to my friend Nikhil's essay about the aging process - almost. Indeed, it is true that aging does not merely consist of a gradual decrease in productivity and energy, but rather, the gaining of wisdom and experience, forming closer relationships with loved ones, and becoming more comfortable with one's self. But what Nikhil actually said was that during the last twenty years of life, one is exhausted and fails to pursue new endeavors - not necessarily true in all cases. So while these points you make are valid, it is still UrRong to think that this invalidates his entire analogy.
Nikhil's point was that sleepiness is a gradual process that can be applied to the aging process. With this in mind, consider how accurate his description is of the first sixty years of life: during the first twenty years of life, we're productive and curious; at forty years old, we're still working hard and time is passing faster than we expected; by sixty years old, we're generally tired. Yes, there are many who remain productive and engaged well into their later years and gain wisdom and experience. But at the same time, aren't those productive individuals still somewhat in denial of their age? Don't they sometimes forget what time it is or feel tired after a hard day's work? The beauty of Nikhil's analogy is that it captures the universal battle between our body's desire for rest after a long life and our minds yearning for more.
I can say with a smirk that I'm confident Nikhil was right when he wrote that the jury is out as to what exactly happens next. While aging certainly consists of many things besides diminishing energy and productivity, Nikhil never said it was only those two things - UrRong! So while it may seem like his analogy misses the mark, his analogy actually hits its target perfectly. After all, we're all going to sleep eventually...and hopefully we won't miss it!