My ‘Sweater Theory’ in Practice

A class I took in law school discussed the efficient-market hypothesis, which holds that an asset’s current share price reflects all available information. After patiently listening to students’ discussion of the various forms of the hypothesis, our guest lecturer delivered an unforgettable line.

He was chief financial officer of a public company and had a German accent. He dryly said he appreciated the exchange among young legal minds, but after decades in finance to him it amounted to saying, “We know it works in practice, now let’s see how it holds up in theory.” He became my front-runner for funniest German economist.

As I’ve grown older, I’ve realized my hypothesis-discussing professor was right. It’s educational and joyful when a trusted authority confirms the theory behind a good you’ve long practiced.

This has happened to me twice in recent years, both as a father trying to raise good children and as a Christian trying to get to heaven. When any of my admittedly fortunate kids has voiced an opinion to the effect of “everything would be perfect if only X,” they invariably confront their dad’s “sweater theory” of life.

The sweater theory reminds that life is an all-or-nothing proposition, an inestimable gift with no “if onlys.” Like pulling on the loose thread of a sweater, a seemingly innocent endeavor risks entirely unraveling the pullover, leaving things not slightly better but dreadfully worse.

Imagine my joy to learn that in “Orthodoxy,” G.K. Chesterton’s apologetical masterwork, he warned the following: “Do not free a camel from the burden of his hump; you may be freeing him from being a camel.” There was my sweater theory pithily stated.

I’ve embraced theory later supporting practice on my own spiritual journey. “Fake it till you make it” is motivation I draw on frequently when I know the good I’m supposed to do but in my weakness, I don’t feel like doing it. What a comfort to discover that before I was born, C.S. Lewis had already provided the underpinnings for this philosophy.

In “Mere Christianity,” Lewis advised: “Do not waste time bothering whether you ‘love’ your neighbor; act as if you did. . . . When you are behaving as if you loved someone, you will presently come to love him.” What a confirmation: Not only might the faking it be brief, the making it might carry me all the way to heaven.

It is thrilling when sound theory holds up in practice. It is scarcely less wondrous when sound practice holds up in theory.

Mr. Kerrigan is an attorney in Charlotte, N.C.