If Sherlock Holmes were to share an insight, you’d pay attention, right?

That’s what I would do. Dr. Watson, the famous detective’s longtime assistant, would listen up as well. “I have not lived for years with Sherlock Holmes for nothing,” he says in one of the classic stories by Arthur Conan Doyle.

So let me serve as a conduit for Holmes, passing on a piece of wisdom drawn from one of his tales and applying it to the economics of the 21st century: The great investigator was a friend of free trade.

We know this from a passage in “The Hound of the Baskervilles,” a novel published in 1902. I’m familiar with the plot mostly from the 1939 film starring Basil Rathbone. I watched Rathbone’s movies as a teenager and haven’t stopped. When they turn up on television today, I’m likely to get lost once more in a great story of mystery, science, and deductive reasoning.

“The Hound of the Baskervilles” involves the death of a man outside his English mansion. It looks like a possible heart attack, but other evidence points to a spectral hound that, according to local legend, haunts the nearby moors. The plot involves family secrets, hidden identities, a prison break, and more.

Early on, Holmes must decipher a threatening note, comprised of words clipped from a newspaper. He consults a recent edition of the Times of London. “Capital article this on Free Trade,” he says. Then he reads aloud: “You may be cajoled into imagining that your own special trade or your own industry will be encouraged by a protective tariff, but it stands to reason that such legislation must in the long run keep away wealth from the country, diminish the value of our imports, and lower the general condition of life in this country.”

It sounds like a line that could have appeared on one of our own editorial pages yesterday, in a commentary on the Trans-Pacific Partnership or a free-trade agreement between the United States and the European Union.

When Holmes finishes the passage, he poses a rhetorical question: “What do you think of that, Watson?” he asks. “Don’t you think that is an admirable sentiment?”

Then his mind rushes forward, as he makes connections between the letter and the mystery of the hound. The subject of free trade doesn’t come up again. It stays on the far periphery of the case.

And yet the curious incident proves beyond any reasonable doubt that Holmes is a supporter of free trade.

Holmes, of course, would warn us not to take our policy cues from the opinions of fictional characters. He’d want us to look at the facts. “There is nothing like first-hand evidence,” he says in “A Study in Scarlet.”

It’s elementary: Data show that free trade boosts economic prosperity, reduces poverty, creates jobs, upgrades labor standards, lowers infant mortality, lengthens life expectancy, and improves international security.

All of this is especially true for the United States, which is the world’s top trading nation. Our exports of goods and services are worth more than $2 trillion per year, and they support more than 11 million jobs.

These are cold, hard facts—the kind that Holmes used to solve his cases. “It is a capital mistake to theorize before one has data,” he says in a story. “Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.”

Anybody who makes an honest effort to study the facts of free trade will discover that the flow of goods and services almost always helps people. This is not to say that nobody comes under pressure from new competition—just that we cannot allow special-interest protectionism to limit the opportunities of the overwhelming majority of Americans.

Critics of free trade are always welcome to change their minds. “I confess that I have been blind as a mole,” admits Holmes at one point. “But it is better to learn wisdom late than never to learn it at all.”

I’ll put it more bluntly: It’s time for the foes of free trade to get a clue.

John Rigolizzo, Jr. is a fifth generation farmer, raising fresh vegetables and field corn in southern New Jersey. The family farm produces for retail and wholesale markets.  John is a volunteer board member of Truth About Trade & Technology (www.truthabouttrade.org)

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