This is one of those super obvious things that you realize after years of bumping up against it:
The price of stocks is a look into the future. You sell it based on what you think it’s going to be worth, you buy it for what you think it’s going to be worth. Either way, its present price is a reflection of a future price. Moreover, these predictions become reality the more people make the same prediction.
There’s not too many things I can think of that are so strongly tied to a future state.