Who said "Gratitude is owed only to one's own strength."?

This quote is attributed to Green Goblin.

Gratitude is owed only to one's own strength. - Green Goblin

"Gratitude is owed only to one's own strength."

Green Goblin Gratitude

"Out, am I?"

"You know how much you've sacrificed to fight me? Everything! But the cunning warrior survives by admitting what he is."

"The cunning warrior survives by admitting what he is."

"I'm something of a scientist myself."

"Gratitude makes life richer."

"A grateful heart is a happy heart."

"Respect those who came before us."

"Life's greatest treasures are the people we love"