A blonde walks into a department store one afternoon, casually browsing the shelves when something shiny catches her eye. It’s sleek, silver, and mysterious. Curious, she flags down a store clerk.“Excuse me,” she says, pointing, “what is that shiny thing over there?” The clerk smiles politely. “That’s a thermos.” She tilts her head. “A thermos? What does it do?” “It keeps hot...