Imagine your body knew how to write. It doesn’t complain. It doesn’t threaten. It doesn’t demand. It simply keeps a diary. Silently. For years. Every cell remembers. Blood vessels — they are like an old city map, where every cigarette leaves a small mark that says "narrowing here." The lungs keep count: each smoke break is a tiny scar, invisible today, but ten years from now they will layer into a dense fabric that no longer knows how to breathe. The heart doesn’t just keep the beat — it tallies the extra work: how many more pumps were needed to push blood through thickened, sticky red cells. You don’t feel any of this. The body is too polite to complain about small things. It stays quiet when you pour carbon monoxide into it instead of oxygen. Silently, it changes the makeup of your saliva, making it more acidic — your teeth will crumble later, but not right away, so you’ll never make the connection. Silently, it teaches your arteries to tighten just a little faster than they should, because they have grown used to defending themselves against what you inhale. The problem isn’t that one day there will be a heart attack or cancer. The problem is that ten years before that, you will already be living in a version of yourself that operates at seventy percent capacity. Tired. With muted taste. With breath that others have grown accustomed to but never mention. Your body keeps this diary every second. It will not forgive you, nor will it seek revenge. It will simply, one day, present you with the final balance — when it is far too late to rewrite the numbers. The only way to leave this envelope unopened is to stop adding new lines to it.