Who said "Change is the only constant for a true fighter."?

This quote is attributed to Goku.

Change is the only constant for a true fighter. - Goku

"Change is the only constant for a true fighter."

Goku Change

"I am the hope of the universe. I am the answer to all living things that cry out for peace."

"Even the strongest of opponents always have a weakness."

"I'm not fighting to win. I'm fighting because I have to."

"The difference between our power levels are like the difference between a firefly and the sun."

"Change brings new opportunities."

"Every day is a new opportunity."

"Healing doesn't mean forgetting."

"You either get better or you get bitter."