I enjoyed reading this passage by Thích Nhất Hạnh, in which he eloquently expresses a phenomenon we can all relate to:

"I have a photograph of myself when I was a boy of sixteen. Is it a photograph of me? I am not really sure. Who is this boy in the photograph? Is it the same person as me or is it another person? … 

The body of the boy in the photograph is not the same as my body, now that I am in my seventies. The feelings are different, and the perceptions are very different. It is just as if I am a completely different person from that boy, but if the boy in the photograph did not exist, then I would not exist either. 

I am a continuation like the rain is the continuation of the cloud. When you look deeply into the photograph, you can see me already as an old man. You do not have to wait fifty-five years. When the lemon tree is in flower, you may not see any fruit, but if you look deeply you can see that the fruit is already there… [I]f the lemon tree has time it will express itself in lemons.” 

Thích Nhất HạnhNo Death, No Fear: Comforting Wisdom for Life (2003)