Dan Gilbert, author of "Stumbling on Happiness," challenges the idea that we'll be miserable if we don't get what we want. Our "psychological immune system" lets us feel truly happy even when things don't go as planned.

The way we fish for popular seafood such as salmon, tuna and shrimp is threatening to ruin our oceans. Paul Greenberg explores the sheer size and irrationality of the seafood economy, and suggests a few specific ways we can change it, to...