Indeed, bull markets are fueled by successive waves of prior skeptics finally capitulating as their fears fade. Eventually, fear turns to euphoria, and that's the stuff of bubbles.
When the economies of emerging markets don't just grow but beat expectations, there's scarcely a mention.
I've long loved emerging markets airlines because they usually sell at bargain prices. The troubled history of developed market airlines unfairly taints these stocks. In the emerging world, they're growth stocks.
Back in the '60s and '70s, data were scarce, and while analysts knew that companies with fat gross margins lagged those with thin gross margins early in bull markets - and overachieved in the later phases - they couldn't do much about it.
In the world I've known most of my life, old stories quickly lose their power over capital markets and get replaced by new surprises. That which everyone fixates on gets priced into the stock market quickly and can't drag on.
The bubble, as investing phenomenon, has been well studied ever since the 17th-century tulip bulb frenzy. Its counterpart in bear markets is not well understood.
The latter part of bull markets are typically led by stocks that are seen then as high quality, but the ones that do best are the ones that weren't seen as such high quality before.