"You can't beat the market -- dollar cost average into index funds" is the sentiment I get from this thread, and also the one I agree with. Actively trying to pick stocks, unless you have extreme interest, ability, and resources to do so is hard. Betting on, basically, "the whole stock market" is a pretty good idea, or at least better than letting inflation take daily bites out of your cash. This is one where I think the received, mainstream wisdom (diversify, invest-don't-trade, investing should be boring, etc) is basically right.

Ponzi schemes can go up exponentially, until they're suddenly at zero.