I'm 73 now. If life is like high school, then I suppose I'm a senior. I believe that our lives are visible to some greater intelligence as a complete inverted parabola, where the apogee is the midpoint. That's the high point of one's life, although one cannot know it at the time, toward which one grows and organizes oneself from the first instant of life. It is when each person reaches their greatest potential. The trip downhill from there to the endpoint is a process of losing energy and dissolution, until we reach zero energy and return to a timeless existence like a photon.
It was writer and cartoonist Allen Saunders (Mary Worth, Kerry Drake, Steve Roper…) who first said in 1957 in a Reader's Digest article, “Life is what happens to us while we are making other plans.” The “other plans” are the business and maya that consume our attention, while “life” is the actual purpose of our being here: our loves, our hearts, beauty, breath, our dreams - everything that matters to us in retrospect as our energy wanes. That purpose seems to be inherent to existence even if we don't see it. Our lives are like green meadows through which we build roads with fences alongside them. While we drive along, we sometimes remember that we have already reached our destination: the beautiful meadows just beyond the fences.