Doc Brown

"A person is smart, but people are dumb."

"I've got to hand it to you, you're a pretty brave kid."

"All we need is a little plutonium."

"This temporal displacement has created an incredible opportunity for us."

"The mind is a terrible thing to waste."

"I must warn you, traveling through time is dangerous."

"Your future hasn't been written yet. No one's has."

"Nothing is impossible if you put your mind to it."

"We're scientists, Marty. We don't concern ourselves with politics."

"The outcome of this moment will affect the future."

"I didn't invent time travel. I improved it."

"Marty, you're my best friend, and I can't lose you."

"The question is not whether we can, but whether we should."

"History is not a fixed point. It's a river, constantly changing."

"Your son turned out to be quite a character."

"Time is a precious commodity."

"Great Scott, what have we done?"

"The future is what you make it."

"We must be careful not to create a paradox."

"Science is about asking the right questions."

"I've spent thirty years preparing for this moment."

"The DeLorean is the key to our success."

"Never give up on your dreams, Marty."

"This is absolutely fascinating from a scientific standpoint."

"We're not just changing history, we're writing it."

"The consequences of our actions ripple through time."

"Stay focused, Marty. We don't have much time."

"Your mother and father are meant to be together."

"This is the most important moment in both our lives."

"I believe in you, Marty. You can do this."