In 1973, Buffett made a $10.6 million investment in the Washington Post Co. Just over 10 years later, as he explained in his 1985 letter to shareholders, the investment sank to a market value of about $8 million, a loss of nearly 25 percent. At a glance, it was a crushing defeat for a then still-rising investment manager.

But Buffett, perennially patient, was unfazed. In the same letter, he told his shareholders not that the investment was a bad idea, but that, "What we had thought ridiculously cheap a year earlier had become a good bit cheaper as the market, in its infinite wisdom, marked WPC stock down to well below 20 cents on the dollar of intrinsic value."

Buffett told his shareholders, "You know the happy outcome." Shortly after Buffett invested his millions and the market decided to keep selling, Kay Graham, then CEO of the Washington Post Co., "had the brains and courage to repurchase large quantities of stock for the company at those bargain prices" — a result of the inexplicable fire sale — "as well as the managerial skills necessary to dramatically increase business values."

The rest, in retrospect, is history. The company's market value soared. According to Buffett's calculations in 1985, Berkshire Hathaway proceeds from the investment totaled $221 million, some $160 million greater than the same investment in "any of a half-dozen media companies that were investment favorites in mid-1973″ would have yielded. By 2013, Berkshire's 1.7 million shares in the Washington Post Co. were worth nearly $1 billion.

1) This teaches us to follow Buffett's example and buy more PTSC stock.

2) This teaches us to follow Buffett's stock picks.