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How Does an Exception Prove a Rule?

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Here are a few things that have recently been called “the exception that proves the rule”: the Mini-Transat sailing race  (because it’s international and doesn’t “boil down to duels between French sailors”), Adrian Peterson (because his success as a football player is not about “opportunity and scheme” but unusual talent), and a congressional compromise on student loans (because a congress reached a compromise!). Taken as a set phrase, “the exception that proves the rule” indicates a deviation from the norm, a challenge to the stereotype. It says, in effect, the norm or stereotype is the rule and here is something that is an exception to that rule. But wait, how does the exception prove the rule? Wouldn’t it do just the opposite? Doesn’t it prove that the rule does not hold for all cases and is therefore not a rule at all?

It is sometimes argued that the confusion over this expression stems from the wrong understanding of “prove,” that “prove” here means “test,” as in “proving ground” or a printer’s proof. The idea is that the exception tests the validity of the rule, and that test could either leave the rule intact (if some kind of explanation can be found) or overturn it. However, it’s hard to come up with an example where that is truly what is intended by the phrase. It almost always carries the assumption that the rule remains intact.

In fact, the “prove” part of the phrase was not very important in its original formulation. The expression comes from the Latin legal principle exceptio probat regulam (the exception proves the rule), also rendered as exceptio firmat regulam (the exception establishes the rule) and exceptio confirmat regulam (the exception confirms the rule). The principle provides legal cover for inferences such as the following: if I see a sign reading “no swimming allowed after 10 pm,” I can assume swimming is allowed before that time; if an appliance store says “pre-paid delivery required for refrigerators,” I can assume they do not require pre-paid delivery for other items. The exception here is not a thing but an act of excepting. The act of stipulating a condition for when something is disallowed (or required), proves that when the stipulated conditions do not hold, it is allowed (or not required). The general rules are that swimming is allowed before 10pm and that pre-paid delivery is not required. The fact that exceptions to those rules have been stated confirms those rules hold in all other cases. The full statement of the principle reads exceptio probat regulam, in casibus non exceptis. The exception proves the rule in cases not excepted.

These days, you’d have to be one heck of a stickler to insist that “the exception that proves the rule” only be used in its original Latin sense. It has probably come to its current sense through some blending with the expression, “every rule has an exception.” Most of the time, when people say something is “the exception that proves the rule,” they could just as well say it’s “an exception to the rule.” I would argue, however, that “the exception that proves the rule” does more by highlighting the unusualness of the exception. The Mini-Transat, or Adrian Peterson, or a Congress reaching an agreement are not just outside the norm, they are so far outside the norm they force you to notice what the norm is, or that there is one at all. There is an important kernel of the original sense here. The existence of the exception gives force to the rule. The no swimming after 10 pm sign makes it clear that it’s okay to swim before that. The congressional compromise on student loans makes it all the more clear that congress can’t compromise on anything else. Sure, there’s usually a good bit of hyperbole going on when someone pulls out this expression, but that doesn’t mean it doesn’t make any sense.

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Why Are Mugshots Made Public Before a Suspect is Convicted by the Court?
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Jennifer Ellis:

Several reasons.

1. Mugshots can help find people when they have absconded, or warn people when someone is out and dangerous. So there is a good reason to share some mugshots.

2. Our legal system requires openness as per the federal constitution, and I imagine most if not all state constitutions. As such, this sort of information is not considered private and can be shared. Any effort to keep mugshots private would result in lawsuits by the press and lay people. This would be under the First and Sixth Amendments as well as the various Freedom of Information Acts. However, in 2016 a federal court ruled [PDF] that federal mugshots are no longer routinely available under the federal FOIA.

This is partially in recognition of the damage that mugshots can do online. In its opinion, the court noted that “[a] disclosed booking photo casts a long, damaging shadow over the depicted individual.” The court specifically mentions websites that put mugshots online, in its analysis. “In fact, mugshot websites collect and display booking photos from decades-old arrests: BustedMugshots and JustMugshots, to name a couple.” Some states have passed or are looking to pass laws to prevent release of mugshots prior to conviction. New Jersey is one example.

a) As the federal court recognizes, and as we all know, the reality is that if your picture in a mugshot is out there, regardless of whether you were convicted, it can have an unfortunate impact on your life. In the old days, this wasn’t too much of a problem because it really wasn’t easy to find mugshots. Now, with companies allegedly seeking to extort people into paying to get their images off the web, it has become a serious problem. Those companies may get in trouble if it can be proved that they are working in concert, getting paid to take the picture off one site and then putting it on another. But that is rare. In most cases, the picture is just public data to which there is no right of privacy under the law.

b) The underlying purpose of publicity is to avoid the government charging people and abusing the authority to do so. It was believed that the publicity would help protect people. And it does when you have a country that likes to hide what it is up to. But, it also can cause harm in a modern society like ours, where such things end up on the web and can cause permanent damage. Unfortunately, it is a bit of a catch-22. We have the right to know issues and free speech rights smack up against privacy rights and serious damage of reputation for people who have not been convicted of a crime. The law will no doubt continue to shake out over the next few years as it struggles to catch up with the technology.

This post originally appeared on Quora. Click here to view.

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What Happens When You Flush an Airplane Toilet?
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For millions of people, summer means an opportunity to hop on a plane and experience new and exciting sights, cultures, and food. It also means getting packed into a giant commercial aircraft and then wondering if you can make it to your next layover without submitting to the anxiety of using the onboard bathroom.

Roughly the size of an apartment pantry, these narrow facilities barely accommodate your outstretched knees; turbulence can make expelling waste a harrowing nightmare. Once you’ve successfully managed to complete the task and flush, what happens next?

Unlike our home toilets, planes can’t rely on water tanks to create passive suction to draw waste from the bowl. In addition to the expense of hauling hundreds of gallons of water, it’s impractical to leave standing water in an environment that shakes its contents like a snow globe. Originally, planes used an electronic pump system that moved waste along with a deodorizing liquid called Anotec. That method worked, but carrying the Anotec was undesirable for the same reasons as storing water: It raised fuel costs and added weight to the aircraft that could have been allocated for passengers. (Not surprisingly, airlines prefer to transport paying customers over blobs of poop.)

Beginning in the 1980s, planes used a pneumatic vacuum to suck liquids and solids down and away from the fixture. Once you hit the flush button, a valve at the bottom of the toilet opens, allowing the vacuum to siphon the contents out. (A nonstick coating similar to Teflon reduces the odds of any residue.) It travels to a storage tank near the back of the plane at high speeds, ready for ground crews to drain it once the airplane lands. The tank is then flushed out using a disinfectant.

If you’re also curious about timing your bathroom visit to avoid people waiting in line while you void, flight attendants say the best time to go is right after the captain turns off the seat belt sign and before drink service begins.

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