Carl Sagan

"The universe is far larger and older than our ancestors imagined."

"We have obligations to future generations."

"The scientific method requires openness to being wrong."

"Music and science are both ways of understanding the universe."

"We must teach people to think, not what to think."

"The laws of nature are the rules that govern existence."

"Wonder is the beginning of wisdom."

"We cannot solve our problems with the same thinking that created them."

"Adventure awaits those with curious minds."

"The universe does not care about our opinions."

"Courage is facing fear with understanding."

"We are products of the universe knowing itself."

"Mathematics is the language of nature."

"Our common humanity transcends national boundaries."

"The future depends on what we do in the present."

"Imagination will take you farther than knowledge."

"We must be skeptical of authority and dogma."

"Life is precious because of its rarity and fragility."

"The cosmos teaches us humility and awe."

"We have the ability to shape our future."

"Kindness is a mark of strength, not weakness."

"Time is the measure of all things."

"The search for meaning is uniquely human."

"We are caretakers of this precious blue dot."

"Dreams inspire us to reach beyond our grasp."

"Health of mind requires health of body."

"History teaches us lessons we often ignore."

"Work that matters feeds the soul."

"War solves nothing; understanding solves everything."

"Leadership requires courage and vision."