Imagination will often carry us to worlds that never were. But without it we go nowhere.

More from Cosmos

• If you wish to make an apple pie from scratch, you must first invent the universe.
• We are like butterflies who flutter for a day and think it is forever.
• Anything you don't understand, Mr. Rankin, you attribute to God. God for you is where you sweep away all the mysteries of the world, all the challenges to our intelligence. You simply turn your mind off and say God did it.
• "Every government that prepares for war paints its adversaries as monsters," she said. "They don't want you thinking of the other side as human. If the enemy can think and feel, you might hesitate to kill them. And killing is very important. Better to see them as monsters."
• Every government that prepares for war paints its adversaries as monsters, she said. “They don’t want you thinking of the other side as human. If the enemy can think and feel, you might hesitate to kill them. And killing is very important. Better to see them as monsters.”
• If we like them, they're freedom fighters, she thought. If we don't like them, they're terrorists. In the unlikely case we can't make up our minds, they're temporarily only guerrillas.