Banksyhttp://newsvote.bbc.co.uk/1/hi/entertainment/arts/2018739.stm
Variant: Some people want to make the world a better place. I just wanna make the world a better-looking place. If you don't like it, you can paint over it!
Source: Wall and Piece (2005)
“If you want to make the world a better place
Take a look at yourself, and then make a change.”
Source: Song Man in the Mirror
Context: I'm starting with the man in the mirror
I'm asking him to change his ways
And no message could have been any clearer
If you want to make the world a better place
Take a look at yourself, and then make a change
Help us to complete the source, original and additional information
Michael Jackson 110
American singer, songwriter and dancer 1958–2009Related quotes
Source: Your Forces and How to Use Them (1912), Chapter 3, p. 49

Source: Song Song Man in the Mirror

With My Own Two Hands.
Song lyrics, Diamonds on the Inside (2003)
Source: As remembered by Don Redelmeir, Michael Lewis, "The Undoing Project: A Friendship that Changed the World". Penguin, 2016 (ISBN 9780141983035).
“There's nothing more dangerous than someone who wants to make the world a better place.”
Existencilism (2002)

[NewsBank, 03I, Science Guy Wants You to Ask, 'Why?', The Columbus Dispatch, Ohio, October 24, 2001, Connie A. Higgins]

“You might not believe it… but you make the world a better place when you smile.”
Variant: The world is a better place when you smile
Source: The Guardian