Who said "I've learned that love is the most important thing."?

This quote is attributed to George McFly.

I've learned that love is the most important thing. - George McFly

"I've learned that love is the most important thing."

George McFly Love

"I'm your density. I mean, your destiny."

"This is heavy."

"There's that word again, 'heavy.' Is there something wrong with the Earth's gravitational pull?"

"I'm not very good at science."

"I love my wife, but sometimes she drives me crazy."

"Love conquers all obstacles."

"Love is patient, love is kind."

"I'm not stupid, I'm just in love!"