"If winter comes, can spring be far behind?" Who said that?

This is what the English romantic poet Shelley said.

When the cold winter comes, everything withers when the cold wind blows, giving people a bleak feeling. But don't forget, after winter, spring comes. At that time, the sun was shining, the grass was growing and the warblers were flying, and everything was revived and full of vitality.

People who live in darkness and pain, don't forget to look for the light of hope, and don't forget that after darkness is dawn.

This poem was written during the English Revolution. So "If winter comes, can spring be far behind" is written for people living in a dark society. Don't give up hope, bravely fight against the dark reality and win the light of victory.