When you look more generally at life on Earth, you find that it is all the same kind of life. There are not many different kinds; there's only one kind. It uses about fifty fundamental biological building blocks, organic molecules.
Carl SaganMy deeply held belief is that if a god of anything like the traditional sort exists, our curiosity and intelligence is provided by such a God. We would be unappreciative of that gift if we suppressed our passion to explore the universe and ourselves.
Carl SaganThe secrets of evolution are death and time-the deaths of enormous numbers of lifeforms that were imperfectly adapted to the environment; and time for a long succession of small mutations.
Carl SaganAny faith that admires truth, that strives to know God, must be brave enough to accommodate the universe.
Carl SaganThe gears of poverty, ignorance, hopelessness and low self-esteem interact to create a kind of perpetual failure machine that grinds down dreams from generation to generation. We all bear the cost of keeping it running. Illiteracy is its linchpin.
Carl SaganOne of the reasons for its success is that science has a built-in, error-correcting machinery at its very heart. Some may consider this an overbroad characterization, but to me every time we exercise self-criticism, every time we test our ideas against the outside world, we are doing science. When we are self-indulgent and uncritical, when we confuse hopes and facts, we slide into pseudoscience and superstition.
Carl Sagan