There are some issues on which everyone thinks they’re an expert. This explains why today’s New York Times article in defense of the Knee Defender has a couple hundred comments so far.

The Knee Defender was invented by a guy who was tired of people in front of him reclining their airline seats so far back that they made uncomfortable contact with his knees. You attach the thing to the tray table and it stops the seat in front of you from reclining. This made the news recently when a one passenger (a man, presumably tall) used the Knee Defender and another passenger (a woman, presumably not so tall) retaliated with a cup of water. The flight was diverted and both passengers were kicked off the plane.

Speaking as someone who is taller than average and has avoided coach only two or three times in his life, I can understand the motivation behind the Knee Defender. It’s bad enough with the limited legroom in coach without the person in front of you reducing your space even more. I’d never use the Knee Defender, however, because a more civilized approach is to communicate one’s discomfort to the reclining passenger in front of you, hoping thereby to evoke a sympathetic response. Also, life is too short.

Speaking as someone who doesn’t run an airline, I can also understand the motivation behind cramming as many passengers as possible into an airplane. There is efficiency (mostly $$$) at stake.

Nevertheless, if airlines are going to limit legroom, they need to limit how far back seats can recline. Otherwise they’re inviting conflict between their customers. Seats that can recline way back are an obsolete technology from a time when flying was one of those enjoyable experiences relatively few people ever had.

Of course, the airlines could simply rely on the common sense and common decency of their passengers. There are people who ask the person behind them if their reclined seat is causing a problem. There are other people who tell the person in front of them in a nice way that their reclined seat is too far back. People do these things.

But then there are other people who shouldn’t be allowed out in public. Many who responded to the Times article argued that they have a right to recline their seats as far back as they will go. If they’ve paid good money for a seat that can recline 30 degrees, they are damn well entitled to recline their seats 30 degrees, no matter what effect it has on the person sitting behind them. In effect, people (some of whom used their real names) made this claim: If an airline has given me the ability to do X, I have the right to do X.

Of course, most of us understand that “can” does not imply “should”. Airlines make it possible for passengers to throw water on other passengers, but passengers shouldn’t do that. Airlines also make it possible for their customers to lock restroom doors and occupy those rooms for hours at a time, but their customers shouldn’t do that either.

To be fair, the Times article these readers were responding to was a defense of the Knee Defender. So maybe they got carried away and went overboard when they wrote their unthinking responses. It’s clear, however, that although everyone may think they’re an expert on a topic like this, that isn’t really true.