This is the beginning of sadness, I say to myself,
as I walk through the universe in my sneakers.
It is time to say good-bye to my imaginary friends,
time to turn the first big number.
It seems only yesterday I used to believe
there was nothing under my skin but light.
If you cut me I could shine.
But now when I fall upon the sidewalks of life,
I skin my knees. I bleed.
From Billy Collins, ‘On Turning Ten’