In many cultures it is customary to answer that God created the universe out of nothing. But this is mere temporizing. If we wish courageously to pursue the question, we must, of course ask next where God comes from? And if we decide this to be unanswerable, why not save a step and conclude that the universe has always existed?
Carl SaganBut I try not to think with my gut. If I'm serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble.
Carl SaganThe fact that someone says something doesn't mean it's true. Doesn't mean they're lying, but it doesn't mean it's true.
Carl SaganIf we can't think for ourselves, if we're unwilling to question authority, then we're just putty in the hands of those in power.
Carl SaganThere are many instances in science, where those closest to the intricacies of the subject have a more highly developed sense of its intractability than those at some remove. On the other hand, those at too great a distance may, I am well aware, mistake ignorance for perspective.
Carl SaganHe sought a way to preserve the past. John Hershel was one of the founders of a new form of time travel.... a means to capture light and memories. He actually coined a word for it... photography. When you think about it, photography is a form of time travel. This man is staring at us from across the centuries, a ghost preserved by light.
Carl Sagan