"Yesterday When I Was Young" 是由Paul Simon和Art Garfunkel共同創作並演唱的一首歌曲，收錄於他們1973年的專輯《Bridge Over Troubled Water》。
這首歌的歌詞如下：
Yesterday, when I was young,
Life was so much simpler then.
We didn't know about the future,
We didn't know about tomorrow.
Yesterday, I was so much younger,
I could do anything I wanted.
I didn't know what I was gonna do,
I didn't know what I was gonna be.
The world was so much smaller then,
And life was so much sweeter then.
We didn't know about the future,
We didn't know about tomorrow.
Now I'm older, I'm wiser,
But I still don't know what tomorrow brings.
I'm still trying to figure out,
What it was that I really wanted.
And if you were here with me now,
Then maybe I wouldn't be so confused.
But then again, maybe not,
Because maybe I wouldn't need you anymore.
Yesterday, when I was young,
Life was so much simpler then.
Now that we've all changed and grown up,
Yesterday's gone and tomorrow never comes.