Appeal to tradition

“Since the garden opened”

At a community garden meeting, a new member suggests watering in the early morning instead of the evening. The coordinator replies: “We’ve watered at six in the evening since this garden opened in 1988. That’s how it’s done here.”

The reply gives the practice’s age and nothing else. Whether morning or evening is better is a question about the plants, the weather and who’s available to do the watering. Nearly forty years of watering at six doesn’t show that anyone ever compared it with watering at dawn. A habit can last that long just because it was never challenged.

“Cooks have done it for generations”

“Never wash a cast-iron pan with soap. Cooks in my family have looked after their pans that way for generations.”

This one sounds like hard-won experience, and it may be. But the long practice shows that the rule was passed down, not that it was tested against the dish soap in today’s kitchen. A rule can outlive the conditions that produced it. Whether soap harms the pan’s coating is a question about what happens to the pan, and it can be checked directly.

“We’ve never done that”

A neighborhood association plans its summer picnic. Someone proposes an online sign-up form alongside the paper sheet at the library. The chair says: “We’ve run this picnic with a paper sheet for thirty years. We’ve never done online sign-ups.”

Here tradition is used to reject something rather than to defend it. The chair doesn’t say what would go wrong with an online form. The fact that nobody tried it before isn’t evidence that it would fail; if anything, it means there’s no record either way.

Stated bare, the argument leaves out the only thing that could connect a practice’s age to its merit:

The added premise is a factual claim, and it’s where the argument is won or lost. It can fail in several ways: the alternatives were never tried, the practice is younger than it seems, or the conditions it was tested under have changed.

• Wisdom of our ancestors: earlier generations believed it, so it’s right. Jeremy Bentham gave this name to one of his “fallacies of authority” in 1824; it treats the people of the past as authorities. “The founders of this club would never have allowed it.”
• The dismissive form: rejecting a proposal because it breaks with tradition. “We’ve never done it that way.” Bentham’s reply to the fear of anything new still works: “Whatever is now establishment was once innovation.”
• Appeal to common practice is its present-tense relative: something is widely done, so it’s acceptable. That counts people rather than years, and it’s covered under the appeal to popularity. The names overlap in some references; Bjørn Hofmann’s paper, for instance, lists “appeal to common practice” among the other names for the appeal to tradition.

The family. The appeal to tradition has close relatives that also use an idea’s date in place of evidence about it. They differ in whether the idea is old or new, and whether its age is counted for or against it:

In any choice between an old option and a new one, the diagonals amount to the same bet. Defending the old and rejecting the new both assume that earlier is better; praising the new and dismissing the old both assume that later is. Hofmann, analyzing the arguments over a new cancer treatment, suggests that the case for it tended to rest on an appeal to novelty, and that the appeal to tradition is the typical flaw in skeptics’ arguments against new technology.

A practice’s age isn’t a reason by itself, but what long use has shown about it often is.

• The question is about the tradition. What a custom is, how a holiday is usually celebrated or what a ceremony involves is settled by what has been done. When continuity is the point, as with a wedding custom kept because earlier generations kept it, “it’s always been done this way” is the answer.
• Long use has tested it, under conditions that still hold. William Harpine argues that traditions often preserve good solutions even when nobody remembers the reasons, and that the case for deferring to them is strongest where conditions have been stable and alternatives have been tried and dropped over time. It’s weakest where circumstances have changed, where the tradition is recent, or where alternatives were suppressed rather than tested.
• As a starting presumption, not a proof. Keeping an arrangement that works until someone gives a reason to change it is sensible, because change has costs. Even Bentham, who attacked “the wisdom of our ancestors” at length, wrote that “provisional adherence to existing establishments” is grounded on “considerations much more rational” than deference to the past. The error is treating the presumption as an answer to the reasons that are offered.
• As a reason to find out why before changing it. Not knowing what a long-standing practice is for isn’t evidence that it’s for nothing. This is the idea behind Chesterton’s fence.

The test: is the argument pointing to what long use has shown, or only to how long it has lasted?

The drawer joint

A furniture maker explains why she still uses dovetail joints on drawers: “A drawer gets yanked open thousands of times. This joint has stood up to exactly that in furniture that’s hundreds of years old.”

She mentions age, but as a record of a test. Generations of drawers have been pulled the same way, and the joint has held. Nothing about how drawers are used has changed. She isn’t claiming newer joints are worse, only that this one has a long track record at this particular job. This is the tested, under conditions that still hold condition above.

A day on the cart

A new library volunteer wants to skip a step: returned books sit on a cart for a day before they’re reshelved. A longtime staff member says: “We’ve done that for as long as I’ve worked here, and I don’t know why. Let’s ask the branch manager before we drop it.”

The staff member doesn’t argue that the step is right because it’s old. They argue that a long-standing practice may have a reason nobody remembers, and that finding out is cheap. If the reason turns out to be obsolete, the step can go. This is the find out why before changing it condition above.

Deferring to tradition is often a good bet. Most people can’t work out from scratch why every custom, recipe or rule exists, and Harpine argues that practices refined over generations can sometimes hold more knowledge than experts reasoning from scratch. The same argument sets the limits: a practice is tested only against the conditions it grew up in, and a tradition that exists only because powerful people imposed it hasn’t been tested in the way that matters.

Bentham thought the phrase “the wisdom of our ancestors” misleads through a trick of language. We call earlier generations “old,” which suggests experience, but they lived before us and had less experience to draw on, not more. “What in common language is called old time,” he wrote, “ought... to be called young or early time.” He also noticed who reaches for the argument most readily: people with an interest in preserving an established abuse. The Stanford Encyclopedia of Philosophy’s entry on fallacies summarizes his concern as debaters resorting to the authority of traditional beliefs instead of considering the merits of the reforms in front of them, which is why the appeal to tradition sits close to the appeal to authority.

• Ask what the long use has shown. Were other ways tried and dropped, or was this simply the first way that stuck?
• Ask whether the conditions have changed. A practice can be the right answer to a problem that no longer exists.
• Ask what it’s for before removing it. If nobody knows, find out; if the reason is gone, say so.