Life runs on carbon because carbon chemistry clears every gate a living system must pass. It forms bonds that are stable yet easy to rewrite, builds a huge variety of structures and functional groups, recycles cleanly through carbon dioxide, pairs well with water, and can store information while also copying itself. Silicon makes bonds too, but on Earth it tends to lock into rocks rather than cycle through living things. Here is a question most of us never stop to ask. Why carbon, and not silicon? Your body runs on carbon. So does every tree, whale, mushroom, and bacterium, and so did the first cells billions of years ago. Proteins,…