Everyone is entitled to their own opinions but not their own facts, the late senator Daniel Patrick Moynihan once declared.

One wonders what the senator would think if he listened to America’s national debate today. People of all persuasions are finding their own facts and ignoring ones that don’t fit their view of the world.

In today’s information age, there exists infinite series of statistics on nearly any subject, so the search for facts that support your ideas is relatively easy. Take the debate over the Affordable Care Act, which may be history by the time you read this.

In Arizona and many other states, premiums reportedly doubled. In Kentucky and Washington, they allegedly went down. As someone who has been contributing to employee-sponsored health insurance for 30 years, I find it hard to believe they ever went down, but I haven’t kept close tabs.

Interviewing value investing legend Jeremy Grantham for this month’s cover story proved to be an enlightening experience. In person, he is very different from the supremely self-confident, erudite writer that he appears to be in public.

Facts, however, are of paramount importance to Grantham, and his recent writings have irritated many other value investors. Among the most vociferous is Jim Grant, the gifted financial writer and eternal skeptic. There are very few observers of the financial world I’d rather read than those two gents, and I suspect they both enjoy trading barbs.

In a world changing as fast as the present one, defining value is very hard. Some people call Facebook a value stock.

Several years ago at our Inside Alternatives conference, Grant recommended Russian gas giant Gazprom as a great value. He noted that it was selling at three or four times earnings with a dividend near 7%. And that was after all the Russian oligarchs had looted the company.

It’s hard to argue that Gazprom isn’t cheap. However, some value investors who care about corporate governance and accounting integrity might well have other issues.

And as Grantham says, if you don’t believe the price levels of equities have changed over the last 20 years, just look at the facts.

Email me at [email protected] with your opinion.