For and/or Against Method, initial miscellany

The past couple weeks I’ve been accumulating material related to our fledgling summer reading group. First I got For and Against Method, realized it was more for than against so I ordered the third edition of Against Method and also found the (apparently much shorter) first edition online.

I’m currently dipping my toes into For and Against, reading Lakatos’s lectures at LSE on the scientific method. I was expecting to be more interested in Feyerabend’s perspective, but so far I’m pleasantly surprised. Lakatos is an interesting guy, and the conversational tone of the (transcribed) lectures is delightful.

I’m not sure how we plan to do this reading group, so, anarchist that I am, I’m going to randomly lash out until something sticks! Here are some initial thoughts from Lakatos’s first two lectures:

The past couple weeks I’ve been accumulating material related to our fledgling summer reading group. First I got For and Against Method, realized it was more for than against so I ordered the third edition of Against Method and also found the (apparently much shorter) first edition online.

I’m currently dipping my toes into For and Against, reading Lakatos’s lectures at LSE on the scientific method. I was expecting to be more interested in Feyerabend’s perspective, but so far I’m pleasantly surprised. Lakatos is an interesting guy, and the conversational tone of the (transcribed) lectures is delightful.

I’m not sure how we plan to do this reading group, so, free-wheeling anarchist that I am, I’m going to randomly lash out until something sticks! Here are some initial thoughts from Lakatos’s first lecture:

  • Around pp. 24-25 he lays out the demarcation problem: we want a (set of) method(s) to separate good and bad science. Presumably, our method should stand up to its own scrutiny. If our method is L(t), taking theory t and returning “good” or “bad”, then L(L) should return “good”. To me, this looks Gödelian.
  • p. 26: “I remember when back in my Popperian days I used to put this question to Marxists and Freudians: ‘Tell me, what specific historical or social events would have to occur tin order for you to give up your Marxism?’ I remember that this was usually accompanied by either stunned silence or confusion. But I was very pleased with the effect.

    “Much later I put the same question to a prominent scientist, who could not give any answer because, he said, ‘of course anomalies always spring up, but somehow sooner or later we always solve them.’ This is why, according to Feyerabend, who follows in Popper’s footsteps, all these criteria for intellectual honesty have one and the same function: they are empty rhetoric to frighten school children.” [emphasis my own]
    • Anyone here know something about rhetoric and the Greeks? Personally, I’m drawn to the notion that it’s all basically rhetoric. The term I prefer, though, is bullshit. Don’t get me wrong, by BS I don’t mean “wrong” or “bad” (per se). And for that matter, I don’t quite mean rhetoric either. It’s something like the sort of communication that goes on during a poker game.
      • You might be able to see that I’m going to be naturally sympathetic to Feyerabend who, apparently, preferred to think of himself as an entertainer than an academic philosopher. That’s part of the reason I’m reading Lakatos first. But I’m happy to see that a) Lakatos has a sense of humor, and b) He’s got a character endorsement from Feyerabend.
    • There’s good BS and bad BS. Bad BS leads to things like advertising campaigns and college accreditation schemes. Good BS leads to open minded learning. Good BS is what happens between grad students in a good program after midnight.
    • Good BS isn’t arbitrary, but it isn’t too tightly bound to reality either. You can’t send an astronaut to space on good BS, but you probably need good BS to come up with the idea in the first place.
    • I’m a materialist at the end of the day, and I believe in an objective external universe (though I can’t reject a Cartesian evil genius). But my map of that universe is highly impressionistic. I think anyone who’s map is more precise is either fooling themselves, or highly specific (i.e. they’re missing out on something).
    • Currently, I’m thinking rhetoric is for strangers and BS is for friends.
  • Lakatos talks about three basic groups: Militant positivists, anarchists, and elitist authoritarianism.
    • The positivists would be right if they were omniscient. In principle we could come up with theories that perfectly aligned with reality. And we could come up with a theory of theories that neatly separated the good from the bad. But the universe is more complex than our finite minds can handle.
      • Did you hear the one about the economist who was told about the latest brilliant new business? His response: “sure it works in practice, but does it work in theory?”
    • Lakatos’s view of the anarchists is that different theories are essentially all at the same level, but some get more support and others get less.
    • According to the elitists “there is a demarcation, but there are no demarcation criteria.”
    • I’m basically an elitist-anarchist with a heavy dose (I hope) of humility. There are better and worse theories (it’s not quite “anything goes”), and often (but not always) the elite are in the right position to pass (fallible) judgement. If a professional economist (ahem) says “Theory X is stupid”, then odds are good they’re correct. But it’s not guaranteed. Not even if all economists agree.
  • There’s no easy way out. Some science is good and some is bad, and there’s no algorithmic way to distinguish them.
    • It’s like the historians’ joke: “What was the outcome of WWII? Too soon to say.” We can extend the metaphor all the way back. It’s too soon to declare any specific outcome to the Big Bang. It’s surely the case that there will be some outcome (according to my materialist, even LaPlacian, priors), but predicting that outcome would require a computer bigger and more powerful than the universe.
  • Fundamentally, distinguishing good and bad science requires going out on a limb, taking a risk, making a judgment. All theories will ultimately be tested against objective reality, but nature isn’t always great about sharing her data and our methods (especially our language, which places the ultimate constraints on our ability to share and accumulate knowledge) prevent us from getting to 100%.

My understanding is that Lakatos will be building up to some notion of a more-or-less objective way to demarcate good and bad science. I believe there is good and bad science, but I’m skeptical of humanity’s ability to draw any sort of hard line separating the two. I think the evaluation of science is more like the evaluation of art than the evaluation of competing answers to a well defined mathematical question.

Sometimes science is more art than science…

Tying this in to my wheelhouse: science (as LaVoie has repeatedly told us) is in a similar position to market enterpreneurship (and also ants, which are amazing) and the Austrian insights apply: this is the sort of stuff that fundamentally only works in a decentralized, anarchic fashion. The ant queen is not actually a central planner. Entrepreneurship is decentralized social learning that central planning is no substitute for. And science is not so comprehensible that we’ll ever find some way to automate approval of grant proposals.

Learning is hard because we’re finite beings staring into an infinite abyss.

Dunbar’s Number

One of my favorite ideas in social science is Dunbar’s number: the cognitive limit to the number of relationships our brains can handle. It’s something like 150. That’s about the number of people our ancestors might have shared their tribe with 20,000 years ago.

Our sense of social propriety is tuned to dealing with people within our circle. Economics often seems counter-intuitive because it’s largely about how to interact with people outside that circle.

Here’s the example I use in class:

You’ve got a date tonight. You stop at a florist to pick out a bouquet and start wondering if maybe chocolate would be a better gift. Dark chocolate or milk? Or maybe something else. You think back to your economics classes and realize that if your date had $20 cash, they could buy this bouquet if it’s what they really wanted, or chocolates if that’s preferred. So when you knock on the door, instead of offering a bouquet, you hold out a crisp $20 bill.

What happens next?

If you aren’t dating an economist, you get the door slammed in your face.

So you run back to the florist, buy the flowers, run back, and nobody answers the door. Your date probably went to the bar with friends. You call a cab. When it pulls up to your door, the fare is $20. You just spent $20 on these flowers. You try to pay for your fare with the flowers.

What happens next?

The driver refuses and insists on cash.

So what’s better, flowers or cash? Is your date irrational, or the cab driver? Neither. Both are rational within the context they’re acting in. The driver is a stranger and market rules are appropriate. In this context, $20 is worth more than $20 worth of flowers. Maybe the cab driver wants flowers, but cash gives them the option to buy whatever best meets their needs.

You and your date were trying to cease being strangers. The cab driver is outside of Dunbar’s number, but your date would have (could have) been inside that inner circle. At that point, the signaling value of the flowers would trump the economic value of the cash.

Economics has a lot to tell us about how to behave with those inside and outside of our Dunbar’s number. But that dividing line calls for different rules on either side: the rules of family and neighbors on one side, and the rules of the market on the other.

I’m thinking about Dunbar’s number because I just finished a recent episode of EconTalk where they talked about a classic example from behavioral economics: An Israeli daycare, tired of late pickups started charging fines to late parents. Ironically, this resulted in an increase in late pickups that persisted even when the policy was reversed.

The daycare example is often trotted out to say “see! Sometimes adding an incentive backfires! Raising the price from $0 to $x increased the quantity of lateness demanded. People are irrational!” Of course it only takes about 5 seconds of thinking to realize that we aren’t holding all else equal here. As usual, there’s a lot of interesting stuff hidden in the ceteris paribus assumption.

The more sophisticated interpretation of this example is that attaching a price shifted parent’s interpretations of the norms. In my language: the inclusion of money in that interaction shifted the rules of behavior from those of neighbors to those of strangers.

(Roberts brought up an important point I hadn’t considered with this example: the price was too low. Prices communicate information about how onerous it is to produce a product, and that price told parents “it’s not a big deal if you’re late…”)

More generally, when we’re looking at some social scientific question, Dunbar’s number demarcates a point separating the assumptions we can make about sharing and monitoring–whether it’s about the practicability of communism (the real kind, not the kind with mass murder), corporate bureaucracy and firm size, or the tenability of informal institutions.

History and Philosophy of Science

Disclaimer: I’m not a philosopher of science by training, but I occasionally play one in the classroom.

The above playlist is* an excellent overview to the issues surrounding the question, “How do you know?”

I first stumbled into the topic of the philosophy of science (PS) as an undergrad at San Jose State. I was required to take an upper-division general elective class from a list of what seemed like tree-hugging indoctrination courses. I don’t remember what the other options were, but this class was probably the most important class I’ve ever taken.

This spring I taught “Modern Economic Theory” which I twisted into a mix of PS and History of Economic Thought. The biggest lesson I wanted to convey was: there are no right answers, there are lots of wrong answers, and our task is to seek the less wrong answers.

From my syllabus:

I hope to convince you of two big ideas:
1. There are no “right answers” but there are plenty of wrong answers.
2. What we know about the world rests on a foundation of received wisdom. And that foundation isn’t always as solid as we’d hope.

The video playlist above does a nice job of shedding light on how and which science is difficult. There is surely some objective truth to the universe, but it’s bigger than we can fit in our limited brains. Trying to understand our universe requires a heavy dose of humility, lest we impose grand plans that make things worse.

*As far as I know… a) See the disclaimer at the top. b) There’s an inescapable irony here. Science is fundamentally about uncertainty, so even if I was a philosopher of science, I wouldn’t be in a position to guarantee anything. See Feyerabend for more details.

Proposal: Let’s stop calling them “Property Rights”

I think an alternative that is both clearer and more general is “Decision Rights”. When I teach Coase Theorem I use both terms, and (I think) students have an easier time grasping it when they realize that property rights are really just rights to make certain decisions. I can’t see a good reason to keep using the term property rights except that by historical accident it’s become entrenched jargon.

Property sounds like “stuff” to most people. And property rights sounds like “owning stuff”. This raises two points that need clarifying:

1. There is more to the world than just the physical, and there is more to property than just stuff.

I would argue that economic rights are human rights. (I would also argue that corporations are owned and staffed by humans but are not humans themselves.) And I would say that right to self-ownership is a particular type of economic/human right.

When we talk about environmental issues, the root problem is usually over some shared resource (e.g. we can’t neatly privatize the atmosphere and let now-private conflicts be resolved in court). It’s much easier to focus in on the relevant particulars when our language directs us to what’s really at stake (e.g. whether I can decide to put more than X amount of pollution into the atmosphere without legal consequences).

2. I own a bit of land and I can make many decisions about how to use it. But I can’t set up a nuclear reactor or burn a massive pile of debris. My ownership is not carte blanche, but a bundle of different rights. I have the right to use (for normal domestic purposes), to exclude, to sell, etc. By “I own” what I really mean is “I can make a particular set of decisions.

I hope my hard core libertarian friends will agree with me that the decisions I can make are not limited by what is explicitly legislated. I suspect my interventionist friends will disagree. But I also think interventionists can agree that it’s more reasonable for me to have a set of decision rights (how ever nebulous the extent of that set is) than some more magical sounding dominion/ownership over a particular fifth of an acre.

The notion of decision rights makes it clearer what political debates are over. If we want to pass a law saying you can’t put a pool in your yard because of spotted owls, “property rights” muddies the discussion. The law would take away a particular property right–which is to say, the right to make a particular decision. But the debate is going to devolve into “you’re taking our land” vs. “no we aren’t.” It’s close to the real issue, but not close enough.

tl;dr: When we talk about “property rights” or ownership what we really mean is a set of various decisions that one has a right to make. Those decisions might be over the use of what we traditionally call property (e.g. my yard), but it might also be over shared resources (e.g. the atmosphere), decisions with collective impacts (e.g. ecosystem management–or lack thereof), or socially constructed issues (e.g. intellectual property). The term “property rights” is not clear or obvious (particularly for people who aren’t already likely to read this blog). A better term would be “decision rights.”

Further thoughts on the carbon tax.

This post is in response to feedback from my previous post on this topic.

There are no panaceas.

But as abstract ideas go, pollution taxes are pretty appealing. Holding constant lots of things that we can’t really hold constant, it means replacing the inefficiency resulting from poorly defined/enforced property rights with a world where prices more accurately reflect the costs of one’s decisions.

Let me come back to the things we’re “holding” constant in a bit. Why do I want to throw my weight behind shifting public perceptions in favor of pollution taxes?

I think they’re underrated by the median voter. Climate change is just a subsidy paid in the form of worse conditions. But most people (including people who should know better) don’t have a good understanding of the problems caused by subsidies.

Which is not to say a carbon tax isn’t overrated by the median policy wonk. There are a ton of important caveats, but on balance, as a policy for use in the next 50 years, I think they’re a useful tool to enhance efficiency or replace worse tools.

Again, there are no panaceas. I’m also not a huge fan of the “Economists’ Statement on Carbon Dividends” as written (for reasons I’ve hopefully mostly addressed). I suspect the best case scenario for my preferred carbon tax policy would be a modest improvement. I think the bulk of the gain would be a cultural shift away from “let’s regulate our problems!” to “let’s leverage incentives to address our problems!” Not Earth shattering, but a step in the right direction.

So let me state my position, then we can dig into criticisms and caveats.

Let’s make marginal shifts away from taxing investment and towards taxing negative externalities. As we go, let’s spend a lot of effort trying to study the impacts and adjust accordingly. Let’s heavily agument that with abatement policies rather than trying to return to some pre-industrial climate target.

Okay, let’s dig into criticisms and caveats.

  1. Public choice considerations
  2. Geoengineering and other alternatives
  3. Cost
  4. Coordination
  5. Uncertainty

1-Public choice considerations

A Green New Deal will be a rent-seeking bonanza. Pollution taxes will face the same sorts of problems that plague the tax code in general. There will be intentional loop-holes and accidental screw ups.

We have to continue to push for reducing the complexity of tax codes in general. But I can’t deny that a carbon tax would be a step back on this margin.

Minus a hundred points for my position.

2-What about geoengineering?

Geoengineering sounds like a possible panacea. Maybe it is. But I’m not willing to flip a switch and find out the hard way all at once.

First off, geoengineering is scary. The climate is a complex system and complex systems are difficult-impossible to manage well. And that’s especially concerning if it means that anyone with a few million bucks can try to fiddle with Earth’s thermostat.

But it seems like a plausible tool that might be used to address climate change. Similar to my take on a carbon tax, I think the way to go is baby-steps plus research.

What about subsidizing “green _____”

Personally, I’m skeptical. Solar sounds appealing, and I (personally) think windmills are beautiful. But I don’t think the government will do a good job of picking winners and losers. Pollution taxes are appealing to me because they don’t require bureaucrats to choose. Again, I think the way to go is to use pollution taxes to offset other taxes–while continuing to advocate for reduced size/scope of government and a return to federalism.

Plus five points for my position.


We should also remember that GDP is an imperfect measure of well being. The current figures aren’t directly comparable to the figures we’d get in a post-carbon-tax world. A one-time fall in GDP doesn’t (necessarily) mean we’ve screwed things up.

A tax big enough to halt climate change would be incredibly costly. Too big a tax yields a negative net benefit.

Still, it’s worth remembering that a) we can go too far with a carbon tax, and b) we don’t have access to a silver-bullet solution. So let’s start small and gradually increase carbon taxes till we get close to (our best estimate of) the optimal level.

Plus epsilon points for my position.


The basic idea of a carbon tax is that we’re dealing with a global-scale externality problem. But small scale taxes are unlikely to do much beyond shifting where pollution happens. A fully effective tax would require multi-lateral coordination. And, as a country, we aren’t very good at that.

Trying to create a tax on imported carbon-intensive goods that didn’t face a tax at home seems a) sensible at first blush, and b) a massive opportunity for public choice problems.

On the other hand, we could justify a tax commensurate with the local impacts (something like 10% of the global impact). This fits nicely with my idea of starting small and adjusting at the margin.

But even within the U.S. there are coordination issues. Long Island will likely face net costs from climate change, but other areas will benefit from a longer growing season.

Plus 10 points for my position, but also minus 10 points.


Uncertainty cuts both ways: we’re currently accidentally manipulating the climate and that could turn out to be catastrophic. Trying to intentionally manipulate it in the other direction is also dangerous. Again, the appropriate focus is on marginal tinkering [much as it clashes with my non-interventionist priors] rather than ambitious global engineering [which grabs my priors by the lapels and knees them in the groin].

When I teach externalities, I draw a graph like this:

Negative externalities when we magically know their magnitude.

In this market, we end up with an equilibrium quantity defined by the point where Marginal Private Cost equals Marginal Social Benefit (MPC = MSB). But the Marginal Social Cost (MSC) is greater, so we get a deadweight loss equal to the triangle I’ve shaded in red and purple.

It’s important to note: we don’t actually know where the MSC curve is. It’s somewhere above MPC, but we’re basically in the position of trying to eliminate a subsidy we don’t know the size of.

The relevant models–climate models and economic models–are filled with uncertainty that we simply cannot resolve without real life experience.

What does the economic way of thinking tell us? Act on the margin. Setting a tax that pushes supply (MPC) up to the green line doesn’t fully address the problem (as I’ve assumed it to be in this graph), but it’s an improvement.

Even better, it’s an improvement where the biggest returns are experienced up front. This modest tax fails to get rid of the red deadweight loss (DWL) area, but it eliminated 3/4 of the total DWL.

Plus X points for my position where X is a random variable with an unknown distribution, positive first derivative, and negative second derivative.


At my friend’s behest I’ve been looking at Bob Murphy’s critique of carbon taxes. I find it’s shifted the magnitude of my prior opinion, but not the direction. I still think carbon/pollution taxes are a good idea, but I no longer think they’re a great idea. My take away from Murphy’s work is that the optimal carbon tax is fairly modest. My response is to advocate for getting a very modest carbon tax on the books, then gradually shift tax policy in that direction.

For climate change (and any other problem) we ought to be pluralists. A mix of approaches is ideal. Part of the appeal of Pigouvian taxes is that they allow and encourage a wide range of responses. The best pollution abatement scheme isn’t something we can look up in a binder. We have to discover it, and crowdsourcing is the appropriate way to do that.

But carbon taxes are only one part. We should also advocate for changes that will ameliorate harm. I am more bullish on these policies than I am on a carbon tax:

  • Make it easier for the world’s poorest people to move to rich countries that will be better able to cope with climate change.
  • Quit subsidizing flood insurance.
  • Quit subsidizing polluting industries (and other industries).

Even though geoengineering scares me, we should try to learn more. Ditto for any other possible tools that come along.

Government isn’t the only problem

Working in a college, I’m at the front lines of a significant problem: wasteful bullshit jobs. In fact, I am writing this post to procrastinate editing a bureaucratic report (that nobody cares about) that has been slowly grinding the joy out of my life for the past several months. I have to write this report for the benefit of regulatory oversight which, ironically, is supposed to ensure that I use my privileged position for the benefit of society instead of wasting my efforts on pointless or destructive outlets.

In my case, this bullshit aspect of my job is a predictable outcome of working in a state sponsored bureaucracy. But the same disease afflicts private industry too.

If I’m the head of a Fortune 500 company, I have incentive to increase profitability of my company, but I have competing interests too. Most importantly I have to maintain my position of power within the company. Bruce Bueno de Mesquita and coauthors have laid out the logic of the situation in The Dictator’s Handbook, and The Logic of Political Survival–in a nutshell, I have to worry about competition for positions of power within any hierarchy. This requires engaging in cooperative rent-seeking to keep the right people happy. If I don’t, I risk losing my position to a sycophant who will.

We shouldn’t be surprised to see Niskanenian logic show up in these situations. Corporate flunkies are like a private army that can help me keep my position of power even if they don’t contribute to the profitability of the firm. Even if I want to maximize profits, if I have to worry about keeping my position, I have to engage in some of this costly, inefficient rent-seeking.

In other words, “firms maximize profit” is an approximation that brushes aside methodological individualism. Don’t get me wrong, there’s evolutionary pressure on firms that will push in that direction. But within a firm there’s evolutionary pressure preventing the firm from fully maximizing. (In other other words, if I survive this report I’ll have to start reading up on corporate governance.)

This logic is a natural source of bullshit jobs, even in a free market. Regulatory capture should make it worse, but we’ll never completely eliminate it.

On a more speculative note, I think we also have to worry about culture. For one, our current culture drives the demand for increased regulation. For another, we prize work for work’s sake to the point that most people would rather see someone fritter away their brief experience as a sentient being than see them fail to live up to social expectations. Such notions, I think, are behind the surprising lack of riots in the street you might expect in a world where most people know we face this problem of bullshit jobs. But I’ll leave any further speculation for the comments.

tl;dr: Our economy is beset with bullshit jobs that sap our creative capacity and crush our souls. And pretty much everyone knows it. Government is part of the problem, partly because regulation creates demand for paper-pushing, and partly because anti-competitive regulation converts lively, profit-seeking firms into private bureaucracies in their own right. But there are deeper problems: our willingness to abide, and the fundamental logic of hierarchical organizations.

RE: Economists’ Statement on Carbon Dividends

I just got an email asking me to sign on to an open letter arguing for some carbon tax policies. I’m seeing some push back from (smart, economically literate) Facebook friends, but I think it’s a viable step in the right direction.

Here’s the statement paraphrased:

We think global warming is an important and urgent issue and we recommend these five things:

1. A carbon tax is the best, most cost-efficient way to do as much about carbon as needs to be done. [For a given level of carbon reduction, I agree. How much carbon reduction should happen (and how much at government behest) I am deeply agnostic about.]

2. We think this should be phased in over time and should be revenue neutral. [Yes on both points, but the rest of the statement makes it seem like they’re talking about a pretty short time horizon. I’m not sure how fast is too fast, but I’m sure there’s such thing.]

3. A carbon tax is more efficient than a set of specific regulations. [Certainly!] It’s also less likely to be subject to changing political winds. [Is it though?]

4. We should also apply a carbon tax to imported goods. This would reward energy-efficient American firms and prod other countries to follow suit. [Hmmmm… I can’t really disagree with the general principle, but this sounds like it will require bureaucratic oversight that will be subject to regulatory capture. On the other hand, we’ve already got that.]

5. We should give the revenue collected back to U.S. citizens, to offset increases in energy prices. [Okay, but if it’s going to be revenue neutral and come with a transfer scheme, that’s going to take some detangling!]

I buy into the notion that carbon emissions create large scale externalities that will probably be more bad than good on balance. Not universally bad, mind you. And not something that humanity won’t ultimately adapt to. But I think the people who will face the brunt of the bad outcomes will be the world’s poor (who we should help migrate to better climates!).

I don’t think we can just impose “the right” carbon tax and have everything come out just right. Even though I routinely draw out the case with a supply and demand graph in class, the truth is that nobody has access to those curves in real life. But a small tax can serve to reduce the inefficiency of pollution even if we don’t get it exactly right.

The revenue neutral part is important–we’re currently taxing lots of things we actually want more of (like investment). So if we can cut those taxes by taxing things we want less of (pollution), we’re reducing two sources of inefficiency in the current setup. Of course you and I have bolder views about what policy should look like in 100 years, but restricted to a 10 year window, a revenue neutral carbon tax looks pretty good to me.

The letter dramatically over-simplifies things. Climate change is probably a problem, but probably not as big a problem as proffered by proponents of proposals to prepare for apocalypse. It’s not clear to me that we have a good idea of a) all of the effects (good and bad), b) how people will adapt, and c) how people will adapt to a changing policy regimen.

Figuring out how to handle the tax on imports will be difficult and rife with rent seeking. Unmentioned is the impact on exports. If all our trading partners follow a similar policy, there’s no problem, but in the mean time there’s a tension that will probably be resolved with some unfortunate bit of rent seeking.

I’m sure most reasonable people would agree that instantaneous change would probably be unduly costly, but it’s not clear what the right speed of implementation is.

There are some miscellaneous rhetorical points I have issue with, but I suspect those are in there to throw a bone to people who aren’t me.

I hope that 10 years from now this open letter looks a bit silly. But I also hope that 10 years from now pollution taxes start to replace more inefficient taxes. On balance, I’m happy to see the letter prodding us in that direction.