Money Talks: Philosophy of The Budget

Summary

---

Slate Money: Money Talks – "Philosophy of The Budget"

Host: Felix Salmon
Guest: Barry Lam (Host, Hi-Phi Nation podcast)
Date: June 10, 2025

---

Episode Overview

In this episode, Felix Salmon sits down with philosopher and podcaster Barry Lam to unpack the philosophy that underpins public discourse and policymaking around the federal budget—specifically the meaning of deficit projections and the different baselines used in budget debates. Venturing deeply into the philosophy of language and the problem of induction, the conversation connects academic skepticism to very real consequences for public policy.

The two explore how definitions, assumptions, and seemingly neutral language can be manipulated to create confusion or justify partisan policy stances, using the U.S. Congressional Budget Office’s (CBO) budget "scoring" process as a case study. They draw on 20th-century philosophy, bringing thinkers like Nelson Goodman and Saul Kripke into dialogue with present-day fiscal politics.

---

Key Discussion Points & Insights

The Problem: What Does "Deficit Goes Up" Mean?

• Budget Chaos Context: The conversation is set against the backdrop of ongoing budget debates in Congress, with politicians making conflicting claims about what various tax and spending bills "do to the deficit."
• Superficially Simple, Fundamentally Complex: While people talk about the deficit increasing or decreasing as if it's straightforward, Felix and Barry show the complexity underneath such claims.
• Economic Projections & Assumptions: Predictions about future deficits depend on underlying, unknowable economic forecasts (growth, interest rates), which both hosts agree are always wrong to some degree.
  [04:10] Felix: "Let's just stipulate for the time being that we have no idea what the future holds."

The CBO's Method: Baselines and Hypotheticals

• Comparing Alternate Futures: The CBO compares two hypothetical futures: one with the new bill and one under "current law." The difference between the two is claimed as the bill’s effect on the deficit.
  • [09:19] Barry: "You're not comparing, like, 2026 to 2025. You're comparing two different 2026 worlds."
• Current Law vs. Current Practice: Republican lawmakers often challenge the CBO’s "current law" baseline, advocating for a "current tax rates" baseline which makes tax cut extensions seem less costly.
• Time-Limited Legislation Traps: The 2017 Tax Cut and Jobs Act (TCJA) included tax cuts set to expire in 2025 to minimize their scored cost, creating artificial cliffs in budget projections.
  • [12:35] Felix: "Current law, when it comes to taxes, is pretty much the law of land as passed in...the Tax Cut and Jobs Act of 2017."

Philosophical Puzzles: Goodman’s "Grue" and More

• Goodman's "New Riddle of Induction": The philosophical tension: What predicts the future? “Grue” is defined as “green until 2026 or blue thereafter.” Both “green” and “grue” fit all observations up to now, but they predict different futures.
  • [23:50] Barry: "If this emerald was grue...I would expect it to be blue if I looked at it next year."
  • [25:13] Barry: "Well, you can think of green as a made up property too..."
• Connecting Philosophy to Budget Baselines: The idea of choosing a baseline (e.g., current law, current practice) is analogous to picking "green" or "grue" — neither is the only "natural" choice.
  • [27:18] Felix: "The econo wonks at the Congressional Budget Office basically have to struggle with this...What is the thing that just continues if we don't change it?"

Tactical Skepticism and Alternative Facts

• Weaponization of Skepticism: Philosophical skepticism, once confined to academic debate, now infiltrates political rhetoric as a tool to legitimize or challenge prevailing narratives ("alternative facts").
  • [33:24] Felix: "It definitely reminds me of the whole concept of alternative facts."
• Selective Skepticism: Skeptical arguments are deployed tactically—not consistently—against unwelcome truths, e.g., in denying climate change, vaccine efficacy, or fiscal data.
  • [38:13] Barry: "...it's a very selective kind of skepticism...you deploy this kind of really old style skeptical reasoning, but...only to the kind of things that you want to win against somebody."

The Limits of Argument & When to Call Out Tricks

• Dogmatist vs. Skeptic: Ordinary life can't be lived in a state of perpetual skepticism; some rules must be accepted.
  • [40:04] Barry: "...we haven't come up with a good term for that. My advisor...called it a dogmatist. But a dogmatist, you know, that's not a good word."
• Recognizing Philosophical Tricks in Political Debate: When politicians swap baselines or move goalposts by invoking new standards (e.g., switching from "current law" to "current tax rates"), it's akin to introducing "grue" or "quus" in logic—an attempt to win an argument by manipulating definitions rather than substance.
  • [39:19] Felix: "You can't just change the rules in the middle of the game."

---

Notable Quotes & Memorable Moments

• On the Paradox of Defining Baselines:
  [19:42] Felix: “How do we describe the facts?...the only question is, how do we describe the facts? And this is where I want to bring in your friend and mine, Mr. Nelson Goodman.”

• On Goodman's Riddle
  [23:02] Barry: “So then Goodman constructed this new property...Gru...it’s green and having been observed prior to 2026, or blue after 2026.”

• Making Philosophy Concrete
  [26:38] Barry: “There really are time dependent properties that are perfectly okay. Like...whether computers are Y2K ready or not.”

• On Political Gaming of Skepticism
  [38:32] Barry: “Yeah, that’s exactly what it is. Right. You know, I mean, the right way to respond to this kind of stuff is, oh, you're doing the GRU thing. Okay...you can project anything.”

• Host’s Frustration with Rule Changes:
  [39:19] Felix: “The rules have been set. We are playing the game now...You can't just change the rules in the middle of the game.”

• Practical Advice on Skeptical Moves:
  [40:37] Barry: “When they feel like something is like there’s a trick about what people are saying...you know something is going wrong...if we’re playing that game, we can do the philosophy seminar thing, but ordinary life requires us to have already had a solution to that problem.”

---

Timestamps for Major Segments

• [00:01] – [05:08]: Introduction; why philosophy matters for budget debates; initial definitions of "deficit goes up."
• [05:09] – [11:31]: The CBO’s approach to budget scoring and comparing alternate futures.
• [12:35] – [18:49]: TCJA tax cliffs, Republicans' challenge to baselines, political incentives.
• [19:42] – [27:18]: Philosophy deep dive – Goodman's “grue,” baseline selection, real-world analogies (Y2K).
• [29:22] – [31:44]: Kripke’s Wittgenstein paradox ("quus" vs. "plus"), Quine’s "undetached rabbit parts."
• [33:24] – [38:16]: "Alternative facts", tactical and selective skepticism, skepticism’s influence on political debate.
• [39:19] – [42:39]: Calling out philosophical tricks in politics; dogmatist vs. skeptic; final reflections and practical advice.

---

Takeaways

• Budget discourse is inherently philosophical: The discussion exposes how supposedly empirical questions involve deep philosophical choices about definitions and baselines.
• CBO’s “current law” baseline is a convention, not a necessity; choosing otherwise can dramatically shift perceptions of fiscal responsibility.
• Philosophical skepticism, once academic, is now a tool in political warfare, enabling “alternative facts” and shifting definitions to suit partisan ends;
• Critical thinking requires recognizing when philosophical tricks are deployed for political gain—and being prepared to call them out by returning to agreed rules.
• Ordinary life, and governance, demand a practical dogmatism—not succumbing to endless skepticism, but reasoning from agreed facts.

---

Final Word

This episode serves not only as a masterful entry-level seminar on the philosophy of language and induction but as an urgent reminder that the way we argue about, report on, and legislate the budget is always already philosophical, and vulnerable to manipulation. As Felix wryly puts it, “You can’t just change the rules in the middle of the game.”

Transcript

[A]

Hello, and welcome to Money Talks from Slate Money, the show where I, Felix Salmon, and occasionally my co host, Emily Peck, will talk to the most interesting people in the world about the most interesting things in the world. And right now, quite amazingly and wonderfully, we get to talk to Barry Lam about philosophy. This is a money show, I promise, but this is going to be a very philosophical money show. Barry, welcome to Money Talks.

[B]

I'm so happy to be here. You know, philosophy is polarizing. Either you've turned it off or you're like, oh, that's going to be great.

[A]

Yeah. At this point, the only people still listening are the people who are, like, nerding out and going, this is really cool. So now we can just be total nerds. We are going to talk about all manner of philosophical things and specifically how they apply to the current budget debate. And we bring in some great philosophers, starting with Descartes and Hume and running all the way through Willard Van Ormon Quine and Saul Kripke and other wonderfully named people. It's all coming up on Money Talks. We are kind of sort of colleagues, even though we've never actually met, because you have your very own podcast under the Slate umbrella.

[B]

That's right. I've been here for, what, I don't know, three, four years. So hi Fi Nation. New episodes coming back later on this. I've been gone for a couple years, but happy to have new episodes.

[A]

And that's hi Fi, with a P. That's right.

[B]

H I, P, H I.

[A]

Because apparently if you want to abbreviate philosophy, it becomes phi.

[B]

You could say phi. Which, I don't know what's the proper, like, Latin way? I mean, because it's a Greek letter, but people speak in Latin. I don't know, some people say fi, some people say fi.

[A]

I'm going to have to brush up on my Latin. I am very rusty indeed when it comes to Latin. I'm slightly less rusty when it comes to the philosophy of language. Well, I don't even know if it's the philosophy of language.

[B]

Well, it's both. It's philosophy of language and it's this thing that is. Yeah, it's the philosophy of language or epistemology, you might say.

[A]

I feel like this is a real epistemic problem here, and the problem that we are, that we are struggling with is the very simple or deceptively simple statement that people will make about the budget. Because we are in the middle of budget chaos right now on Capitol Hill, and all manner of tax bills are being proposed and members of Congress are opposing them or supporting them or whatever. Donald Trump wants a big, beautiful bill. And the number one question which people have about this bill, any given bill, is what does it do to the budget deficit, Right? And so people will say something like, it increases the deficit by this much or it decreases the deficit by this much. And it sounds like that is a nice, simple, easy to understand sort of empirical statement. But the more you think about it, the harder it becomes to actually know or understand what that statement means.

[B]

What you're talking about, I think, is also economic projections, period. The idea that you're projecting based on some kind of policy. So the deficit is one kind of projection. It'll do this to the deficit in whatever next year, five years, 10 years. But there's also these other things like we're going to project this kind of economic growth. Growth or something. I think that's the general problem.

[A]

So let's get that one out of the way first, because I think that's the easy one. The thing that everyone understands is that you can't know the future, right? No one knows what the future holds. And so what, you know, the Congressional Budget Office will project certain facts about the future, you know, that we'll have growth of this much, the interest rates will be there, and so on and so forth. And then once those assumptions have been made, they're like, well, okay, if all of these assumptions hold, then the deficit will be this in dollars. And then we can ask, you know, the next question, which we'll get to in a minute, which is, is that higher or lower than it is right now? But before we even get to the is it higher or lower than it is right now, we have to definitely caveat that with assumptions or assumptions, and they are certainly false, and they will, with 100% certainty, either be too optimistic or too pessimistic in terms of economic growth and tax revenues and all of that kind of stuff. And indeed, the Republicans love to come out with their own projections which say, like, oh, you know, growth is going to increase by 5.6% because we're no longer, you know, levying tax on tips. And that means that everyone is going to become a waiter and make lots of money and there'll be a much bigger economy and all of this kind of like crazy assumptions. So let's just stipulate for the time being that we have no idea what the future holds. But there is a projection, there is a forecast, and the question isn't so much will the deficit go up or down but it's more like, assuming that this forecast holds, does the deficit go up or down? Let's put to one side this question of forecast error, because I think that's properly not really a philosophy of language problem.

[B]

Right. Okay.

[A]

And instead, let's concentrate on the other bit of this, the sentence like, you know, under this budget, the deficit goes up, which is the goes up bit. You know, the increase or decrease thing.

[B]

Right.

[A]

So let me just ask you, as a kind of naive observer who occasionally reads the newspaper, how would you define that? What would you consider it to mean if I were to say, under this budget, the deficit goes up?

[B]

So not somebody who studies the economics of the budget, you know, I would have thought there is a portion of the budget that goes to paying off debt, and there's a portion of the budget that goes to pay for other stuff. Social Security and Medicare and the discretional spending and defense spending and so forth. And the deficit is how much we add to the debt every year. That's my understanding of what it is.

[A]

And the amount we add to the debt is only peripherally related to how much we spend paying off the debt. There is this line item as part of the budget, which is debt cell service, which is basically paying interest on the debt.

[B]

Right.

[A]

But the amount that we add to the debt is basically the amount that we spend minus the amount that we receive in tax revenues. And if you wind up spending more than you take in. In. In tax revenues, that delta, that difference is known as the budget deficit.

[B]

So if the deficit goes up, then it's a larger number this year than it is last year. That's like my naive understanding.

[A]

That's a really, really good, sensible. We'll call that a. Yeah, that's right. Which is you just compare the deficit in 2026 to the deficit in 2025, and if the deficit in 2026 is larger than the deficit in 2025, then the deficit has gone up, and we're measuring that in nominal dollars.

[B]

Okay, good. So it's just an absolute number, like the way that I would do my budget, you know, at home. Right. If my deficit this year is larger than the deficit last year, then the deficit has gone up.

[A]

Exactly.

[B]

Okay, so that's only option one.

[A]

Then would it surprise you to learn that naive definition of number go up is not what the Congressional Budget Office, the independent, bipartisan, official arbiter of such matters, determines whether the deficit goes up or not?

[B]

That is not how they do it.

[A]

No.

[B]

Oh, okay. How do they do it?

[A]

Take a guess. Why would you think that they would look at this some other way?

[B]

You know, if I had to guess, I would say it has something to do with acceleration or deceleration or something like that. The way that I would think about, am I going faster than I was five minutes ago?

[A]

You're looking at, like, the first derivative or the second derivative.

[B]

I guess, yeah. My guess is that maybe it's something like that. Maybe if it's going faster than they would do, but that would just be my guess.

[A]

So the answer is interesting. The answer is actually legislative, okay? And what the CBO does is it scores bills. There's a, you know, as we all know, a big, beautiful bill trying to make its way through Congress. And the idea is, does this bill increase or decrease the deficit? And so what you need to do is you need to compare two different things. You need to compare the world with this bill to the world ex ante, as you might say, like the current world, the world that we live in right now without the bill, where the bill has not been passed. So we live in the sort of this kind of, you know, beautiful relapse area and state where the bill has not been passed. And there is something called current law. And then what the CBO does is it looks at a different possible world, which is the world where the big, beautiful bill has been passed. And it says, what is the difference between the deficit in the world where the big, beautiful bill has been passed compared to the current world where the big, beautiful bill has not been passed? And that difference is the amount by which the bill increases the deficit.

[B]

Okay, but they're both future worlds you're comparing. So you're not comparing, like, 2026 to 2025. You're comparing two different 2026 worlds.

[A]

Correct?

[B]

One in which the bill has passed. Okay. I don't understand why they're doing it this way, but I could see how it's different from comparing a 2026 to a 2025 number. You're comparing two hypothetical 2026 numbers.

[A]

So as we have already ascertained, we are like, we are assuming that we know the future. We are assuming that the CBO assumptions about growth and interest rates and unemployment and all of that stuff come to pass. We know for a fact that they won't. But this is just the X hypothesis assumption. And then we're just saying under these assumptions, what happens to the deficit under this bill and what happens to the deficit under current law? And that difference is basically the effect of the bill. And so what you're trying to do. What the CBO is trying to do is basically saying, if you pass this bill, this is the difference that you're going to make to deficit or revenues or whatever next year.

[B]

So I immediately see the problem without knowing anything about the budget. Like, what a philosopher will immediately say is that, look, there are a lot of different hypothetical 2026 worlds, right? And when you said according to current law, but we could imagine different ways of understanding what current law is as you project a possible 2026 world. So I could immediately see that there's so many different ways you can choose a 2026 future world to compare to the big Beautiful Bill World, 2026.

[A]

So you are very smart, Barry, and you are realizing why I got a philosopher on this show to talk about this. Because let's introduce a very important term here, which is baseline. What the CBO is doing is it's scoring the budget deficit, assuming that the big beautiful bill has passed, and then it's subtracting or looking at the difference between that number and some baseline. And the baseline that the CBO uses is this thing called the current law baseline, which basically just says, let's assume that no one passes anything and we just continue with the law as it currently stands. What is the difference? And that is the difference that this bill makes.

[B]

Right?

[A]

And what you said absolutely correctly is, well, there are lots of other possible baselines you could use. You don't need to use current law law. Why would you specifically choose that thing? And in saying that, you are aligning yourself with JD Vance, bunch of Republicans who all say the exact same thing, and they're basically saying, well, why? Why use current law as a baseline? Why don't we do something a bit more intuitive, which is, say, use current tax rates as a baseline. And this is where you, Barry, furrow your brow at me and go, wait, what's the difference?

[B]

Yeah, Well, I can imagine that some differences might be that current laws. I mean, look, this is what I'm imagining, right? Laws are complex. Some laws have provisions in it that expire, some laws that have provisions in it that don't expire. I don't understand. Do current tax rates just continue if the big beautiful bill doesn't pass? I'm not quite sure you are.

[A]

You are asking all the right questions and saying all the right things. Because, yes, it turns out that current law, when it comes to taxes, is pretty much the law of land as passed in something called the TCJA, the Tax Cut and Jobs act of 2017.

[B]

Right.

[A]

Which was passed in the first year of Donald Trump's first term as president. Now, when the TCJA was passed, the CBO did all of its scoring and everything. And as you all remember, if you remember 2017, it was a big tax cut. A lot of people got tax cuts. The standard deduction went up a lot. The top income tax rate came down from, like, 39.6% to 37%, whatever it was. So there were a whole bunch of tax cuts that happened. And the CBO basically said, if you do all of these tax cuts and make them permanent, then the cost will be a gazillion dollars, and you can't afford to do that. And so what the Republicans did when they passed this law was they made sure that the tax cuts were not permanent and that they would expire after eight years at the end of 2025. Why did they do it at the end of eight years? Because they reckoned that Donald Trump would serve two terms as president, and then right around now, like, it would be someone else's problem and he wouldn't be president anymore. It's very weird that you would have someone be president and then not be president and then come back and be president again. That was not completely foreseeable in 2017.

[B]

Right.

[A]

So turns out, whoops, he now basically owns this problem, which is that at the end of 2025, under current law, which is the CBO baseline, all of the tax cuts expire and tax rates go up. So if we go back to your original idea of what does it mean for the deficit to go up or the deficit to go down? Well, under current law, the deficit comes down quite substantially in 2026.

[B]

Yeah, because tax rates go up because.

[A]

All of those tax cuts expire, and so people pay more in taxes, and so the deficit goes down.

[B]

Right.

[A]

And so the Republicans are like, shit, that's. That makes everything look bad to us, because the current law is very sort of fiscally tight. It's really fiscally hawkish. And so what they are trying to do is push something called current practice or current taxes or whatever you want to call it, which is basically this idea that let's compare the big beautiful bill not to current law as the baseline, but to current tax rates as the baseline. And if you use current tax rates and remember, the current tax rates are artificially low because, you know, they were pushed down in 2017 for a fixed period of eight years, and then they meant to bounce back up again. But if you compare to current tax rates, then that makes the fiscal impact of the big, beautiful bill look Much smaller.

[B]

Well, Felix, answer this political question for me. I thought that the Republicans were deficit hawks, so wouldn't they want to say that the bill reduces the deficit? Obviously they also don't want tax rates to go up.

[A]

But it's really hard to be a deficit hawk and not want taxes to go up. But somehow you're right, the Republicans claim to be deficit hawks. And to be fair, there are, I would say, a minority of them who genuinely are deficit hawks. Yeah, the vast majority of them just kind of say, like to take Donald Trump as a prime example, he campaigned on a balanced budget. Basically, there would be no deficits at all. That was his promise on the campaign trail. So that is highly unlikely. I mean, I'm just going to come out and say that's not going to happen.

[B]

Yeah, of course.

[A]

But that's a very sort of deficit hawk position is to say, I'm going to balance the budget. You know who did balance the budget, weirdly, was Bill Clinton. No one's managed it since. But in practice, Republicans tend to not govern as though they were deficit hawks. Republicans do two things. Well, a couple of things that make it very difficult to run small deficits. One is that every chance they get, they cut taxes. And when you cut taxes, that increases the deficit. And then another thing that George W. Bush in particular would do would be to get involved in extremely expensive foreign wars. And those wars tend to increase the deficit because they tend to be very expensive.

[B]

Right.

[A]

And then another thing that Donald Trump did in 2020 was do a massive stimulus plan when the pandemic hit. And that also increases the deficit. So if you look at their actions, they don't tend to care very much about the deficit, certainly since Reagan. And in fact, broadly speaking, it kind of seems as though the Democrats, or at least the kind of Clinton, Obama Democrats, cared more about the deficit than the Republicans. Biden didn't seem to care about the deficit at all. And he was happy, like doing big stimulus programs and all the rest of it. But like, I would hesitate to say that either party is really made up of deficit hawks.

[B]

Okay, okay. Yeah. It's just trying to understand, I'm trying to understand why it is they want to use the current tax rate way to project the deficit. And it helps me understand it if they're not deficit hawks, but at the same time, if they're really good propagandists, they want to say they are, but then run a larger deficit anyways.

[A]

Right, exactly. And the best way to say that you're a deficit hawk while running A big deficit anyway is to use the current tax rate as a baseline rather than current law as a baseline. Because that way you can say, my bill doesn't increase the deficit even if, you know, compared to current law, it massively increases the deficit.

[B]

Okay, there you go now.

[A]

And this is where I come in. And I will mention that there are lots of other ways that you can measure the deficit and whether it's going up or down. Like, one is the intuitive one that you started off this podcast with, which is just like, does it go up or down in dollars from year to year?

[B]

Right.

[A]

Another way is, does it go up or down as a percentage of GDP from year to year? Right. Another one is to just say, basically, the baseline is zero. We should always assume that there should be a balanced budget and the size of. It's just the absolute size of the deficit in any given year that matters, or the over 10 years that matters. There are lots of different baselines you can use, and depending on which baseline you use, that makes the big beautiful bill seem like incredibly profligate and stimulative and full of deficit, or it makes it look relatively sober and sensible and responsible. And so the choice of baseline is absolutely crucial.

[B]

And it's another one of these, like, the facts are the same, but we're talking about a different way of describing the accounting for it, right?

[A]

Exactly, exactly. We are assuming, and this is what we stipulated at the top of the show, which is we are assuming that the facts, we know the facts, we know what the economic outlook is going to be. And then the only question is, how do we describe the facts? And this is where I want to bring in your friend and mine, Mr. Nelson Goodman.

[B]

Mr. Nelson Goodman, right.

[A]

So tell me, who is Nelson Goodman?

[B]

Okay, so Nelson Goodman was a philosopher, mid 20th century philosopher at the University of Pennsylvania, famous for a lot of different things. One of the things he was famous for was, I think he was the first philosophy teacher of Noam Chomsky, A very young Chomsky, when he was an undergraduate at University of Pennsylvania, taught him. And Nelson Goodman, I think Felix, for your purposes, formulated this problem in the 50s, I want to say 40s and 50s. That reminds you of what's happening. I mean, you're reminded of that problem when you're thinking about these kinds of deficit projections.

[A]

The idea is always we have this intuition that if you don't change something, it will just continue. You know, it's the kind of Newton's first law, you know, of philosophy. It's like something like if something exists and it doesn't change, then it will just continue in the same state. And what Nelson Goodman did was he massively problematized that and said, well, basically trying to define what is the same state is much harder than you think.

[B]

So do you want me to describe this little problem that Goodman formulated?

[A]

Yes, do.

[B]

Yeah. So the problem that Goodman formulated is kind of descendant of this older problem that David Hume formulated. And what David Hume formulated was something called the problem of induction. And this is the problem of how you are supposed to learn about the future when you have data about the past.

[A]

Yeah. We assume that the future will resemble the past. If the sun has always risen in the morning in the past, we assume that it's going to rise in the morning in the future.

[B]

Right. And famously Hume claimed, well, you can make such an assumption, but you don't have any rational basis for it. Nothing about reason forces you to conclude that the sun will rise tomorrow.

[A]

This is so Scottish of him. Like, only a Scott would be like, oh, I don't know. You don't really know that the sun's going to rise in the morning.

[B]

So, famous 18th century philosophical problem. And Goodman just starts off by just saying, suppose we just have a solution to that. Suppose, all right, we're not going to be that skeptical about that problem. We're not going to be the Scottish skeptics like David Hume. There's a way of learning about the past and drawing some conclusion about the future. So Goodman claimed there's this new problem, he called this the new problem of induction, where given the exact same data you have about the past, you can make completely contradictory predictions about what the future is going to be like. And all of Those predictions are 100% consistent with the same data. One example that Goodman used is if you have an emerald in your possession and you observe it and it's always been green, you can safely solution to this Humean problem believe that it's going to be green in the future. Right. So that's.

[A]

It seems sensible. If I'm not going to do anything to the emerald, I'm not going to change the emerald. And if it was green yesterday, it's going to be green tomorrow.

[B]

That's right. So then Goodman constructed this new property. He called it gru. Right. The way that you should think about GRU is just it's green and has been observed prior to, since it's 2020, prior to 2026. So every time you look at an emerald, your emerald, including looking at it now, it's grew because it's green and is being observed prior to 2026. But the property for Goodman is look to be grew is to be green and having been observed prior to 2026, or blue and having been observed after 2026. So that's the new property.

[A]

And so if this emerald was grue, and it has always been grue up until now, then basically I would expect it to be blue if I looked at it next year.

[B]

That's exactly right. Just the way that you construct this property, Gru, it's always been Gru, just like it's always been green. So because of the way you constructed it, you will expect it to be blue after 2026. And that's kind of arbitrary how he constructed it. You just have to put a little or after it's green and it's before 2026 or something else, you just add something else to it. And you will notice that the emerald has always been grew in the past. And so you can safely project that it'll be grew in the future, which is completely incompatible with it being green in the future. Right. So that's the paradox. The paradox is now you can conclude that it's green in the future, and you can conclude that it's blue in the future, and you can conclude that it's red in the future or anything, you can conclude that it's not an emerald in the future.

[A]

And the thing which I love about this paradox is that the first thing anyone wants to do when they hear this objection is they want to say, well, that's the dumbest property you can possibly imagine. What kind of a dumb property switches just according to the calendar and like, you know, suddenly it goes from being green to being glue on some arbitrary day on January 1, 2026. That's really dumb. Obviously green is a real property and grue is a made up dumb property. To which Goodman has the perfect response.

[B]

Well, so Goodman says, well, you can think of green as a made up property too, right? So green isn't the thing that appears a certain color necessary. Green is grew and it's before 2026. Or you construct this other property, blean. Right. Blean is the inverse of grew. Bleen would be it looks Blue up until 2026. Right. Or it's after 2026 and it looks green. Right. Then you define green in terms of grew or bleen and you define blue as bleen or grew or whatever and.

[A]

Exactly.

[B]

Yeah.

[A]

I love this so much. So basically everything that we've thought is green, like green suddenly becomes this incredibly artificial property. Which is time based. And green is just anything in the world that is green. Well, that's the craziest thing in the world, because what you're saying is it's gonna Suddenly switch on the 1st of January, 2026 from being gru to being bleen. And if it doesn't do that, then only then are you gonna be right. It needs to make that switch from Gru to Bleen. And so Green and Gru are both, in their own way, if you define them in terms of each other, time dependent properties.

[B]

Yeah, yeah. And you know what, Felix? One of the things I used to tell my students when I used to teach this is that there really are time dependent properties that are perfectly okay. Right. Like, it has nothing to do with Guru Blean. It's not.

[A]

And one of them is the current law of the tax bill.

[B]

But, yeah, yeah, both of you and I are old enough. But there was this property, whether computers are Y2K ready or not Y2K ready. And it was like this thing that we were really concerned about in 1998, 1999, that's a time dependent, probably. It's like it was works and it's before 2000, or it doesn't work and it's after 2000. That's exactly what. That's a GRU property. And Y2K Ready was definitely one of these things that we were really worried about. Let's check these computers and see if they're Y2K ready or not. So the idea of it being gerrymandered or not gerrymandered as a property isn't enough to help us solve this kind of problem.

[A]

Yeah. And so what happens is that the good old econo wonks at the Congressional Budget Office basically have to struggle with this. Right. They have to struggle with this question of what is the human thing? What is the thing that just continues if we don't change it? And what they. What they say is, it's current law, but could they use something else? Could they say current tax rate? Could they say current debt to gdp? Could they say zero deficit? Like, they could say lots of things, and they just need to kind of.

[B]

Pick one and be consistent with it. Do you know the legislative history? Is there a reason why they choose current law that was legislated for the CBO to do that as a baseline?

[A]

So the intuition is, I think, understandable. I totally understand why they picked current law. Because when you introduce a bill to Congress, people want to know, what difference does this bill make? And so the alternative to passing the bill is not passing the bill. And so the question is, like, when you want to know, what difference does it make? You want to know what is the difference between passing the bill and not passing the bill? And not passing the bill means current law. So that's why they choose current law.

[B]

It just so happens that current law can expire. But.

[A]

Well, yeah, I mean, the current law. This is interesting to be. Let's be very clear about this. The current law does not expire. The tax law rate expires, but the law remains the same.

[B]

The tax rates expire. Yeah. Gosh, it seems wide open when you use these different kinds of baselines. The problem that Goodman pointed out is you can the word he used project anything, anything that you want to project. And as if there's not enough incentive for politicians to be able to say contradictory things at once. You know, it's almost like it's built into the logic of actual rulemaking that you're allowed to do that. At least that's what Goodman's paradox is supposed to show.

[A]

Are we now quite quietly grateful that Nelson Goodman never went into politics? Although I guess Noam Chomsky kind of did. Right?

[B]

That's right. So, Felix, if you will indulge me for a second, when I knew I was going to come on and talk about this, I thought, there's another paradox that came out maybe about 20 years later that is 100% the same kind of problem you're talking about. So are you aware of Kripke's Wittgenstein.

[A]

Paradox, or as it's also known, Krippkenstein?

[B]

Yes. Yes. So the plus. I don't even know how to pronounce this. The plus versus quas. So, you know, this was Green versus Gru, and this one's easier to explain. So this is the idea being you watch people do addition their whole life, and you're trying to figure out what's the rule they're following when they're adding these two numbers together. And we conclude, oh, it's addition. It's this rule that takes two numbers and then, like, takes their sum, you know? But what Wittgenstein pointed out was, but it's completely consistent with everything that you observe, that when they get to the bigger numbers, the answer is always five. Right. Because you haven't seen them add Google numbers that big. Right. So everything they've done is consistent with it's plus when it's small numbers, and it's, you know, the answer is five when it's big numbers. And so this New function. We'll just call it quas. And that's consistent with everything they're doing. So maybe we're all just qusing things together, like two quas. Two is four because it's small. Yeah, but it's because it's small. This sounds just like exactly the same kind of thing that you're talking about, too. It's perfectly consistent with all current data that people are going to project in.

[A]

So was it Wittgenstein who came up with quus, or was it Kripke?

[B]

It was Kripken. He has an interpretation of Wittgenstein, but it's really Kripke. It's really Kripke's puzzle.

[A]

I feel like this is the kind of thing that philosophers love coming up with. I remember some deeply buried part of my memory. Quine had this concept of an undetached rabbit part.

[B]

Yes, that's right. That's right. It's a very similar kind of puzzle, which is that you are trying to figure out what a language you've never spoken, and you're just observing the behavior of a community. And they point at what we would call a rabbit. Right. And they say gava gai. And you, like, have hypotheses. What are the various hypotheses of what this word means? One is that it means rabbit. Right. Another one is that it means undetached rabbit parts. And you can't tell the difference between whether they mean rabbit or undetached rabbit parts.

[A]

And I like undetached rabbit parts because it's, you know, it's funnier than querce.

[B]

Right.

[A]

It's important to have a sense of humor when you do in the philosophy of language.

[B]

Yeah. And this is all the same exact time. Right. Same people. Goodman, Quine, Kripke, they were all hanging out. They were all thinking about these kinds of puzzles. And from what you tell me, they've just basically described ways that you can be a propagandist and draw whatever conclusion you want to draw about whether the deficit goes up or down or whatever.

[A]

Let me stop you right there. We're going to take a quick break, and then when we come back, we're going to talk about all of the other philosophers who've been making kind of the same point and what it means to defeat skepticism. Did this line of the philosophy of language ever sort of escape the academy and make it into politics at all, to your knowledge?

[B]

I think, to be honest, that all of these special puzzles from the late 20th century, the more you think about them and the more philosophers wrote about them, the more they all seem to be reducible to a just general problem of knowledge and skepticism, period. Right. That you can always construct alternatives that are completely consistent with everything. You see that the world is radically different. I think that. That the kind of skepticism, selective skepticism, you see a lot in politics and you see a lot in ordinary discourse today.

[A]

It definitely reminds me of the whole concept of alternative facts.

[B]

Yeah.

[A]

Or the idea, going back even further, that weak democratic institutions care about reality, but like strong Republican institutions will create their own reality just by sheer force of will. And there's this slogan which you sometimes hear on the left, much more on the right, like, you're entitled to your own opinion, but you're not entitled to your own facts. Like, facts are some objective thing out there in the world that we all have to agree on. And the pretty standard move in Republican politics since the George W. Bush administration has been basically to deny that and to be like, no, we can just change the facts if we want to because we are in charge.

[B]

Yeah. So I think that sometimes it's even more insidious than just changing the facts. So there's changing the facts, which is literally to deny data by raising skeptical concerns about what the data really shows and so forth. I think there's a kind of insidiousness to the appeal to. So basically this era in philosophy had all of these, like, skeptical worries about a lot of very ordinary common sense concepts like green. But one of them was, for instance, what causes what. It was like this big, huge area in 20th century philosophy that, you know, you can raise very interesting skeptical puzzles about whether smoking really causes cancer or carbon really causes global warming. And these kinds of skeptical puzzles do make it into political discourse these days. I think I was watching something recently about whether rfk, I think RFK says he doesn't think viruses ever cause diseases, something to that effect, that if you look at deaths from COVID or it's always like pneumonia. And so that's the thing that causes it.

[A]

It seems very related to the very popular theory in, you know, parts of Africa 40 years ago that HIV doesn't cause AIDS.

[B]

No, that's exactly right. But there's something in the vicinity that philosophers have talked about which is to cause anything requires a nexus of things to be true. You have to have an immune system. It's got to do something in order for HIV to damage it. And then. But, but like, are you dying of the HIV virus? Well, there's this idea of a secondary infection and so forth, and you can do all that Kind of skeptical, worrying. But when you come out and describe things using ordinary language, there is a way of describing a truth that HIV has never killed anybody. That can be true.

[A]

Yeah. Like every single death is caused by the blood stopping, flowing to the brain. That's basically.

[B]

No, that's exactly right. That's exactly right. So every single death is the result of the human body being so vulnerable. And so it's. That's the problem. It has nothing to. Every single death is caused by not healing from something. Let's put it that way. That's another way of describing it. It's the same family of problems. I think grue is like this. I think quas plus causes and things, all of these weird little skeptical puzzles. It's kind of a reflection of something humans really can do. If you really wanted to sow some doubt about something, you start getting super fancy. You are saying something half true when you say viruses have never killed anybody. Right.

[A]

And like, far from dealing in the realm of Quine and Kripke and Goodman, we're now going all the way back to Descartes and Hume.

[B]

That's right. That's right. I think that all of these problems of the mid 20th century are versions of the same problem. I think it's Descartes, it's Hume, it's reducible to the same kind of skeptical concerns.

[A]

And it's a whole long project in philosophy to sort of defeat skepticism, which will never completely win, and which it kind of seems, given the vibes, it kind of seems that we're losing. Right. The skepticist side is, like, on the ascendant right now.

[B]

Yeah. Except that it's a very selective kind of skepticism. So, like, the problem that goes back to the 16th, 17th century is global skepticism. If you want to be a skeptic about the moon landing, one way to do that is to be so skeptical that you're skeptical about whether you're awake right now. You're skeptical whether the whole world is being hallucinated by you and that we know how to respond to. You're just like, that's kind of like a crazy person. But it's so selective. Right. It's like you deploy this kind of really old style skeptical reasoning, but. But only to the kind of things that you want to win against somebody at in terms of policy or politics. But you're completely credulous about tons of other stuff. You could be completely credulous about hydroxychloroquine or Ivermectin. Right. Just like. But you Deploy, you know, these standards that quantum mechanics can't pass when it comes to the COVID vaccine, for instance. So the skepticism is on the rise. It's the same kind of skepticism that's deployed, you know, like, all the way back to the 17th century, but it's.

[A]

Selective and it's being deployed tactically.

[B]

Yeah, it's deployed tactically.

[A]

That's right.

[B]

Just like the GRU thing, like you're mentioning, like, that's deployed tactically. Right.

[A]

So I think where we end up here is bemoaning the tactical weaponization of skepticism in political discourse.

[B]

Yeah, that's exactly what it is. Right. You know, I mean, the right way to respond to this kind of stuff is, oh, you're doing the GRU thing. Okay, well, if you're doing the GRU thing, then, you know, you can project anything. Like that was the consequence. Right. If you're going to make that move, there's no deficit.

[A]

Exactly. And I think that's exactly the right thing to do. Whenever you hear a politician saying, well, we should use current taxes rather than current law or any such thing, which is basically, listen, you agreed to the rule when you passed the TCJA in 2017. The whole reason why these things are expiring at the end of 2025 is precisely because of those rules. And so the rules have been set. We are playing the game now. We have started the game. The game is ongoing. You can't just change the rules in the middle of the game.

[B]

That's exactly right.

[A]

Trying to talk about, like, does this particular rule set make sense? Is a way of trying to sort of point people at a shiny object off to one side and distract them from the meat of what you're actually trying to do. So anytime people try and change the rules or say that what really matters is something procedural rather than substantive, you're like, yeah, what are you doing here? You know?

[B]

Yeah. Something about gaming things using selective skepticism is happening.

[A]

So what's the opposite of a skeptic, Barry?

[B]

Oh, gosh. Well, we haven't come up with a good term for that. My advisor came up with this term, which is a horrible term. He called it a dogmatist. But a dogmatist, you know, like, that's not a good word.

[A]

So pejorative, right?

[B]

Yeah. So I wouldn't. You know, some people say anti skeptic is like, the right. Is the right word. I really don't know. You know, some people think that the movement called rationalism is a. You know. But I don't. But I'm not quite sure. I know there's like a bunch of Silicon Valley, you know, tech.

[A]

I wouldn't place that lot among the anti skeptics necessarily. But you and I, we are placing ourselves in the dogmatist camp, pejorative connotations notwithstanding and.

[B]

Right.

[A]

We are skeptical of the skeptical move.

[B]

Right.

[A]

Shoot it down wherever we find it.

[B]

That's exactly right. I mean, the right way so like, just to give a heuristic for the listeners is, you know, when they feel like something is like there's a trick about what people are saying, viruses don't cause disease. And then they, you know, the move they're making is that, well, you not healing is the thing that's caused you to die or something like that. You're like, you know, something is going wrong. And I think the right way to do is, oh, you're appealing to this really radical skepticism such that I can conclude that the world is going to explode and not explode in the future. Okay. If we're playing that game, we can do a philosophy seminar thing, but ordinary life requires us to have already had a solution to that problem. Like, we know that there's a solution to the do viruses ever kill people thing. Right. So, like, we don't need to solve the deep Cartesian skeptical problem in order to go about living. I know I don't have to go around proving that I'm not dreaming. Right. Like, we already have that solution. If somebody's playing that game selectively, I.

[A]

Am not a brain in a vat.

[B]

That's right. If somebody's playing the brain in the vat game, pretty soon it feels that way to you because they're arguing these kinds of things that are completely irrefutable. Like, the world is completely different when you're not looking. And maybe when you're looking, it's just one way. You're like, oh, okay, if that's the game we're playing, we can do the philosophy game. But if we're not playing that game anymore, we already think, okay, we already think smoking causes cancer. So whatever cause means, that's what cause means. We already know that their existing law projections have been made about the deficit. And so we're playing that game. That's how I feel about it.

[A]

I think that's exactly, exactly right. Well, I'm glad that we have ended up on the same page here. I feel like this is the obviously correct Bien Ponson Slate group opinion to hold.

[B]

That's right.

[A]

At some point, we will throw this podcast over to the political gabfest and get them to. But for the time being, we have arrived at the correct, the right, correct and honorable conclusion for which Barry lam I thank you very much.

[B]

Thank you for having me, Felix and.

[A]

Hi Fi Nation back in your podcast feed later this year.

[B]

Absolutely.

[A]

Subscribe Wherever you get your podcast, listen now. Thanks to Barry Lamb. Thanks to Shayna Roth and Jessamine Molly and Ben Richmond for producing. And we'll be back on Saturday with a regular Sleep Money.