system
Given the following post, respond as if you're commenting on Reddit:
human
How are stocks basically at an all-time high when the economy is still so sluggish?

Pretty much all indices are showing the value of stocks at an all-time high, yet economic growth is minimal and forecasts are equally bleak.  

Is that kind of relative growth inevitable, regardless of economic performance?  In 30 years, even if we are in the midst of a recession again, will the new base level for the be something like 30,000?
gpt
Stock prices are based on what people think the future of the economy is like, not the present. The price of a corporation's stock is determined by the expected value of its future profits.

This doesn't mean that people's expectations about the future, as reflected by stock values, are right. Stock owners might be over-optimistic. And a lot of variation in stock prices in the short run is also driven by speculation, which can lead to bubbles.