Who said "Everything's impossible until somebody does it."?

This quote is attributed to Iron Man (The Avengers).

Everything's impossible until somebody does it. - Iron Man (The Avengers)

"Everything's impossible until somebody does it."

Iron Man (The Avengers) Inspiration

"I am Iron Man."

"Genius, billionaire, playboy, philanthropist."

"If you're nothing without the suit, then you shouldn't have it."

"I've successfully privatized world peace."

"The best part of living is knowing you survived."

"The world needs heroes."

"Life is too short to live poorly."

"I'd rather be an optimist and be wrong than a pessimist and be right"