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Comment by elil17 | Hacker News Reader

I think that this person does not know what the Jevons Paradox is. The Jevons Paradox is that increasing the efficiency with which a resource is used may increase the total amount of that resource that is used. Consuming more because costs went down isn't the Jevons paradox - it's spending more because costs went down.

So if you give all your coders a great test harness and they run more tests because it takes up less of their time, that's not the Jevons paradox. If you give your coders a great test harness and then they go from spending 10% of work hours on testing to spending 20% of work hours on testing because testing has such a good ROI now, that's the Jevons paradox.

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Jevons Paradox has become a meme lately because it can be used effectively in a particular type of online argument to sound smart and checkmate the other. But as you say, the popular use is nothing mysterious, just microeconomics. At a certain level of technological development, supply and demand curves meet at a point and it yields a price. If technology develops and makes production more efficient, that crossover point moves, and now more demand can be met. The popular meme idea of scoffing at road construction because it will just make more people drive misanthropically ignores that driving isn't purely emissions but it also gets people to places where they want to go, like visiting family and friends or allows them to live at a different place from where they work if that's more affordable or more to their liking. The road capacity led to more cars on the road, but also to more real demand being met. Now of course, there can be such a thing as totally frivolous additional usage, though one needs a specific value system to judge it whether a trip was virtuous or sinful.

Meanwhile real Jevons is a very particular effect that doesn't show up on all road graphs and doesn't simply mean that opening up more lanes will attract more traffic.

>The popular meme idea of scoffing at road construction because it will just make more people drive misanthropically ignores that driving isn't purely emissions but it also gets people to places where they want to go, like visiting family and friends or allows them to live at a different place from where they work if that's more affordable or more to their liking.

People scoff at road construction (or rather, road widening) as a solution to congestion. I don't think anyone is under the impression that kilometers driven would go down as road bandwidth goes up.

>The road capacity led to more cars on the road, but also to more real demand being met.

No, not necessarily. Maybe some people who would have otherwise used public transport opt to drive instead. Making roads wider could literally make them less efficient, in terms of humans moved per hour per meter of width.

> People scoff at road construction (or rather, road widening) as a solution to congestion. I don't think anyone is under the impression that kilometers driven would go down as road bandwidth goes up.

It is a solution to congestion because a part of the past congestion was that people were stuck at home and gave up on the trip overall, because it would take so long.

> Maybe some people who would have otherwise used public transport opt to drive instead.

Then presumably comfort increased. Also, add bus lanes.

>a part of the past congestion was that people were stuck at home and gave up on the trip overall

That's not congestion. If someone opts not to make a trip, or uses a means of transport that doesn't use the road, such as a subway, then they didn't create road traffic. Congestion refers specifically to the failure of traffic to advance at an efficient speed along a thoroughfare.

>Then presumably comfort increased.

Again, "people scoff at road construction as a solution to congestion". Discomfort is not a component of congestion.

My expertise in unrelated things tells me the dunning-kruger effect is in effect.

As the cost of attention goes down, and the cost of communicating bad ideas goes down, capturing attention with bad ideas paradoxically goes up.

Is it just me or is this a pervasive pattern in hackernews... Someone makes a point then someone makes a contrary point and the conversation spirals off with nothing to do with the original post or concepts. I particularly notice this in more controversial posts on politics.

> I think that this person does not know what the Jevons Paradox is.

Actually, Jevons Paradox is a pop-punk band from Birmingham that formed in 1997 but mostly disbanded in 2003 because of creative differences and (unofficially) the lead singers drug problems.

Not a lot of people know that.

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