Spend some time staring at the famous painting "Washington Crossing the Delaware," and you can't miss the ice. It's everywhere. Cold weather became part of Washington's military strategy, says Alex Robb, an educator at Washington Crossing Historic Park outside Philadelphia....

Across history, humans have always been drawn to the idea that love isn't random. In ancient Greece, Plato imagined that we were once whole beings with four arms, four legs and two faces, so radiant that Zeus split us in two; ever since, each...