Dave Grohl posted on his official Instagram account yesterday a photo of a note in barely-legible handwriting. It turns out that he wrote it when he was in ninth-grade.

Grohl’s note from when he was 15 years old reflects on how much change he had gone through mentally and physically. It’s rather profound for a 15-year-old. You can see him starting to develop his focus, which would lead him to become one of rock’s most successful musicians of the ’90s and beyond.

The note reads: I think that in the past year I have changed both mentally and physically. Mentally I have changed quite a bit. When I was 13 or 14, (I’m 15 now) I used to think of everything as one big joke, life was one big party. But, now I approach everything with a more serious approach. School is no longer a social activity. It’s a part time job that requires a lot of attention and a lot of work. Physically, I have changed a great deal. I was about 6 inches shorter 1 year ago and had a different haircut, different clothes etc…. and now that I think about it……. I’ve changed quite a bit. And so, I think that in the future I will change even more, which makes me wonder…… what will I be like in the future?

One user writes, “Hello sir don’t make me cry ??”

Another said, “Future Dave is pretty cool.”

“15 year old you would be proud of you now. you’ve touched a lot of hearts man,” one fan wrote.

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