Rapture of the deep, or nitrogen narcosis (also known as the Martini effect), is a condition that afflicts deep-sea divers, an anesthetic effect caused by a shift in gases at high pressure. At first, the effects are harmless—mild euphoria, a sense of “mastery over the environment.” It’s only when the diver goes deeper that the real danger arises—impaired judgment, loss of control and decision-making abilities. The lesson, the metaphor, is clear. Don’t plumb the depths carelessly. Don’t become reckless with love. The thing about metaphors, though, is not just their convenience. They are intrinsic to the way we understand our world. They come from the heavens and they come from the darkest reaches of the sea. They comprise the invisible web of consciousness and art and obsession and love and wonder through which we make our way here on earth.