A Thought from Frank Holmes, CEO and chief investment officer US Global Investors

When are things so bad that they’re good? One signal is when Jeremy Grantham is buying stocks.

The Boston Globe wrote Friday that the famed value investor—for many years a high-profile bear on stocks—thinks the market may have already taken its hardest hits and now may be trading “exactly at fair value.”

Grantham is saying that in his view stocks are cheaper than they’ve been in 20 years, and that the market will likely fall even further. But that’s not stopping him from buying now.

He sees the best opportunities in emerging markets, Japan and U.S. blue chips. Infrastructure is also catching his eye.

Grantham’s outlook is not all that different from that of Warren Buffett, the world’s foremost value investor. Last month, Buffett predicted that “markets will move higher, perhaps substantially so, well before either economic sentiment or the economy turns up.”

Buffett’s track record speaks for itself. Below is a chart going back more than 40 years that shows he’s been pretty good at spotting when to buy and when to sell.