This is a thought experiment, not a real offer. If someone offers to sell you a $100 dollar bill for $5, you’d take that deal instantly, right? Of course! But suddenly your friend jumps in and offers $10 for the $100 and now you’re in a bidding war.

Here’s…

Sagan's ability to convey his ideas allowed many people to understand the cosmos better—simultaneously emphasizing the value and worthiness of the human race, and the relative insignificance of the Earth in comparison to the Universe. He delivered the 1977…