Won't take nothing but a memory

Memories. I often wonder why is it that memories usually fade away. Is it cause our heads get to crowded and the only solution is to push out the old stuff? Or because we shouldn't dwell on the past? Maybe it's because memories have the power to keep us locked up inside our heads, too wrapped up in them. I don't know. I think memories are unusual, all the same. Powerful, but truly unusual. See, the thing is, memories, they are everywhere. In a diner you once visited 20 years ago, or perhaps at your favorite shoe store. A familiar sight or a lingering scent, will send us falling off a cliff, trying desperately to hold onto anything on the way down.