Nelson Demille said this quote

A lot of who you were in middle age was determined before you had a chance to manipulate, control, or eve understand the things around you. It was no mystery, he thought, why some old people's minds returned to their youth; the wonder of those years, the discoveries, the first experience with the dirty secret of death, and the first stirrings of lust and love were indelible, drawn in luminous colors on clean canvas. Indeed, the first sex act was so mind-boggling that most people could still remember it clearly twenty, thirty, sixty years later.