I'm definitely going to be reading, and will possibly (time permitting) give you a write up over on my blog in the near future.

For opportunity cost, you seem to be saying that for every dollar (or let's say $1 million) to be spent/invested, one should consider all the potential ways in that it could be spent? There would be endless considerations. Does that sound ridiculous?

Yes, this is what opportunity cost means. However, one does not need to spend a lifetime calculating each possible use of capital. In consideration of opportunity cost, one must examine the highest-and-best likely alternative use of that capital.

In other comments you seem to confuse opportunity cost with externalities. I do not advocate using externalities to determine opportunity costs. I think I made that clear in my “urbanism legend” post. I think examining externalities is important, but too subjective to properly internalize.

That said, it is absolutely important to consider the opportunity costs of the land, capital, and taxes that make up the highway system – not just the accounting of it. Does that mean I conclude there should be no highways? No way – I don't see how you draw that conclusion. But, at the margins, some highways should not have been built, or should exist at a lower capacity. This pared-down system could be more optimally utilized to fully capture the opportunity costs.

Keep in mind, I don't advocate destroying what has already been built, unless market forces dictate so. I would just prefer the government planners stop building roads that clearly do not pay for themselves on the margins.

I see big hypocrisy in complaints about highways. The standard of living would be much lower without.

I don't see why you seem to think that we advocate the complete abolition of highways. Under a free-market system, plenty of highways would still exist. Likely, there would be fewer highways in most places, and the system might be laid out in a completely different way.

It is not accurate for you to purport that a free-market system would not have highways, thus it is not accurate for you to compare the opportunity costs of having no highways vs the opportunity costs of the current overbuilt system. It's not a valid comparison. Clearly, the costs of having no highways would indeed be devastating. But, complete abolition of roadways would require a massive intervention into the marketplace by government far greater than the overspending on highways.

Sure alternative other ROIs should be considered for. Will less infrastructure help other areas to be developed? No highways (or fewer) will reduce many factors of the economy. I think we can agree that the current administration’s budget of a 12% of GDP deficit is bad.

BTW, any person, hiring help (ie a maid or a repairman), vs their own pay scale ( be it $20/hour or higher) is a big dif w/gov (mostly thru user-fees) providing infrastructure.

I do not see the difference between opportunity cost of labor and opportunity cost of capital, much less a distinction between “heavy” and “light” capital. They are factors of production and receive a return in exchange for being deployed in an investment.

Yes, obviously agents don't consider *every conceivable* investment alternative. But the opportunity cost principle does not require that they do. Every time anyone declines a profitable investment because there is a potentially more profitable investment, they are thinking in terms of opportunity cost. So it is with highway construction vs. office construction for example, or any other land use a developer may conceive of. Even from a practical perspective, highly liquid and international capital markets allow individual and institutional investors to choose between many, many investment opportunities. This makes the applicability of opportunity cost as a guide for decision-making that much stronger

Highways usually either have built up areas on each side or basically nothing [outside of urban areas], right? Well, there is a gradual transition (& a hodge-podge) going thru the transect, away from the core. So, for alternative uses (opportunity cost), there is potential for more development, between development, or more open space/farms between open space/farms. Either case would not “go” near the other, right? (no ag. in UAs & no random building in rural areas) In each case, there’s not necessarily a shortage of land; it depends—outward is an option, but often zoned against (roads still needed); highways might occupy 1-5% of the area’s land. Still, w/out highways there is a major problem of taking away transportation ability, which severely limits, if not eliminate, the potential value of most nearby land. Sure, there are local roads, which would be really over-burdened. Would you like driving on local roads for many miles with an average speed of 20-30 mph, compared to 40-80 mph on highways?

How did privatizing streets get into this? Imagine collecting money. High-speed freeways are somewhat conducive to being tollways, w/there being limited access, but for other roads, there are many difficulties with collection. London’s congestion pricing cost $300 million to set up the monitoring & collection infrastructure.

What do you mean by the profitability of roads? What’s artificial about a large customer base (ie high density)? Sorry, I fail to see the connection, again, in regards to highways being user-paid & having some gov support. As you are aware, public transit used to be private & profitable, with it replacing the horse. Once individual mobility became faster, more efficient & affordable with the car, people gradually [over decades] chose to use less public transit (<4% now vs ~90% a century ago), meaning, demand dropped, thus no more profitability. You do realize that if you take away government support (~2/3 of cost) for public transit, it is not financially viable? Highways could be 100% user supported with only about $0.40/gallon more gas tax. Yes, there are externalities, which require a far more encompassing view, with every little action causing a reaction & such. Shall we stick mostly to direct costs?

Good point, in that increasing density causes more congestion. City policy-makers often ignore the capacity of existing infrastructure when packing more people in, especially with this dumb growth, CNU (Communist New Union w/ Lord Duany), structured [sometimes ~forced] living pattern, which can still have merits, when freely chosen.

My earlier comments about leftism might have been overboard, but it seems like there is an effort for the gov. to coerce users to pay for indirect costs—many not measureable. How far is the Vienna School ideology to go in having limited government & privatizing most everything? Example, education could be not publicly supported at all. How much more ignorant would our populace be then? I admit, that’s off the topic of transportation, but under the subject of public goods, but then again it is excludable & easily chargeable compared to roads in general (w/out tolls). Sure, the market creates spontaneous order, but there are some guidelines & infrastructure needed to avoid complete chaos.

Also, you’re ignoring the fact that roads become artificially profitable based on density restrictions that are incredibly common in America, even in its largest cities. Density makes roads and cars more difficult (as adding capacity to a roadway is very expensive and almost always involves widening the road, which involves buying shit tons of valuable land), whereas it makes rail much more profitable (since there is tons of excess capacity due to the much smaller footprint that people take up when riding trains as opposed to their own private automobiles).

Both of these things are libertarian arguments, not leftist ones. You associate mass transit with leftism, which sort of understandable given recent history where mass transit is synonymous with public transit, but mass transit wasn’t always “public.” Around the turn of the century, tons of private mass transit companies were in existence, and in fact built the infrastructure (and much more of it that’s no longer in use) that the state has appropriated and now uses as a socialized public transportation network.

Your example of opportunity cost in a person’s money-value for time, is a different aspect of opportunity cost; for one thing, it’s labor, not heavy, long-term capital.

For opportunity cost, you seem to be saying that for every dollar (or let’s say $1 million) to be spent/invested, one should consider all the potential ways in that it could be spent? There would be endless considerations. Does that sound ridiculous?

Maybe, I’m too blunt in making an analogy (ie arithmetic vs algebra) which shows that certain things have been avoided in analysis & happens to be insulting. Like I said, I could type for pages about the errors, nut I try to be brief, which can leave concepts misunderstood. I see big hypocrisy in complaints about highways. The standard of living would be much lower without.