Ghost Tide in the World

Our family has suppressed a "conceptual ghost" for generations. It has no substance, cannot be perceived, and cannot be described. The only way to imprison it is that no one can ever think of it. Once someone recalls its existence, the seal will instantly collapse. Before my grandfather died, he held my hand tightly, his eyes full of fear. He opened his mouth, as if he wanted to warn me one last time. Then I saw the light in his eyes go out. He forgot. And I'm thinking about it now.