Free Thoughts Blog

Just to clear up any misconceptions, I think the minimum wage is an unjust and inhumane public policy. It is morally wrong. I also believe—I hope less controversially—that rape is a serious moral wrong. And no, George, I didn’t need to study history, sociology, or empirical economics to come to that conclusion.

I suppose George Smith thinks he has snared me in some sort of philosophical trap by forcing me to admit this. After all, in my original essay on the libertarian Non-Aggression Principle (NAP), I criticized devotees of the NAP for the casually a priori approach they often take to issues like the legitimacy of public roads, public schools, and the minimum wage. But—A-ha!—if I don’t think that careful empirical study is necessary to determine the injustice of rape and child molestation, then how can I simultaneously hold that it is necessary in order to determine the injustice of the minimum wage? Gotcha!

Well, maybe it doesn’t sound quite so much like a gotcha when I put it that way. Is it really so absurd to believe that the immorality of rape is considerably easier to discern than the immorality of the minimum wage? That the latter might require a more careful study of a wider array of empirical evidence than the former? I suppose it doesn’t seem that way to me. Some acts wear their immorality on their sleeve—it is part of “what is seen,” to borrow Bastiat’s famous distinction. With others, and perhaps the minimum wage is one of them, most of the wrongness derives from facts that are “unseen,” and require a bit of careful digging to unearth. Is there really an inconsistency here?

Of course, if you think as I do that coercion is bad, then you’ll think that minimum wage laws are prima facie objectionable even before engaging in this digging. But notice that even in the case of rape, we wouldn’t want to end our analysis here. Rape is coercive, yes. And it involves a violation of one’s property in one’s body. But if this is all we understood about rape, then we wouldn’t have come anywhere close to understanding the full weight or significance of its injustice. We wouldn’t understand the devastating psychological effect that rape can have on a woman. We wouldn’t understand that women are often blamed for their own rape, or the ways our entrenched institutions protect rapists while shaming and silencing their victims. We wouldn’t understand, in other words, why a lot of people think rape is an especially serious injustice, or one that calls for more attention and more action to effectively combat.

Rape is aggressive and a violation of property rights, just like stealing someone’s car radio or imposing a minimum wage law on them. But rape is not just like a minimum wage law. And that is because aggression and property rights are, by themselves, not the only categories relevant to moral or juridical evaluation.

This is a rather obvious point, as far as moral philosophy goes. But it does seem to pose a challenge to those who believe that all the thorny questions of justice can be resolved by the application of a neat and tidy principle like the NAP. If not all aggression is on a par—if some, like rape, is very seriously wrong, while some, like shining a flashlight at your house, is not wrong at all—then why should we believe that the non-aggressiveness or aggressiveness of conduct is anything like a sufficient indicator of its justice or injustice? And why should we believe that aggression (no matter how small) must never be permitted in order to produce any kind of social or individual benefit (no matter how large)?

Smith raises a number of other points in his essay, most of which I won’t be able to address here. Which is just as well, I suppose, since he hasn’t yet managed to develop many of those points himself. He stresses (contra Rothbard) that the NAP is about “force,” not “violence,” but doesn’t bother to explain what he takes the difference between those two concepts to be. He asserts that the NAP is about justice, not about moral permissibility, but again he leaves the difference almost entirely unexplained. Since these distinctions appear to play an important role in Smith’s argument, I assume that he will explain them at some point in his series. But until he does, there is little I can do to respond to them.

Smith concludes his essay by accusing me, somewhat uncharitably, of having engaged in a “hit-and-run” against the NAP. I’m not sure what he was expecting from a 1,200 word blog post. Apparently, criticizing the NAP on a number of grounds isn’t enough—I should have developed and articulated my own alternative theory of libertarianism too. Well, I’m happy to do that, and to discuss in more detail the various topics I raised in my initial post. There is certainly more to say about each of them. So I must object to Smith’s characterization. It’s only a hit-and-run if you hit and then run. And I’m not going anywhere.

There has been much buzz lately in libertarian Internet circles concerning the Non-Aggression Principle (NAP), a favorite ethical maxim adopted by many libertarians in defense of anarcho-capitalism. This increased attention to the NAP is due in large part to Matt Zwolinski’s excellent article articulating many of its counterintuitive implications. Zwolinski recommends that instead of radically editing the principle as stated – that is, instead of adding epicycles to our original understanding of the orbital paths of celestial bodies – libertarians ought to undergo a “Copernican Revolution” by developing a new ethical system to justify our preferred socio-political order. Like any good controversy, there has been much response, most notably by Jason Kuznicki in his equally-excellent essay “Non-Aggression and Billiards.” In this essay I examine Kuznicki’s defense of the NAP, not necessarily as an absolute and inviolable axiom, but at the very least as a strong though rebuttable presumption.

We are all taught that certain things are true when in actuality they are false. We are taught, for instance, that there are three inviolable laws of motion governing all moving bodies in our universe, when in reality things work a bit differently when we start dealing with very small particles. We are also fed exaltations concerning the immutable axioms of Euclidean geometry when such an axiomatic system remains contingent upon a series of assumptions that may or may not hold true. Even so, these kind-of-true-but-strictly-speaking-false principles of physics and mathematics are very useful to us: they can allow us to understand how billiard balls interact with one another, or perhaps they help us find out how much manure we need to help fertilize a 16 foot by 24 foot field.  The NAP, so Kuznicki argues, is of similar value: it gives us a good starting point to help determine when actions are morally right and morally wrong, though some refinement, or “engineering,” might be required for more advanced situations.

But many times Newtonian mechanics and Euclidean geometry are insufficient. Surely the rocket scientist and quantum cryptologist need to go beyond high school mathematics and physics classes in order to do their jobs properly. This, of course, does not change the fact that most people need only an elementary understanding of physics and mathematics to get through their day-to-day lives. But in comparing the NAP to something like Newtonian mechanics and Euclidean geometry, we need to see if the analogy carries over to this corollary: do practical agents, trying to navigate through life, require only the NAP to help guide most of their decisions, or do they need a more robust version of the NAP – or perhaps a new moral system altogether – in order to navigate life’s imbroglios? As practical agents, are we high school students or rocket scientists? 

I contend that we are rocket scientists. We are rockets scientists not because life is that hard a thing to navigate through (though it certainly has its harsh contentions), but rather because the high school math many libertarians want us to adopt – the NAP – is so insufficient as a moral theory that it cannot stand up to the basic experiences we all, as practical agents, face. For example, most of us, it seems reasonable to suggest, will end up having and raising kids. Will the NAP (Newtonian physics) tell us how to raise them right? As Zwolinski points out, it will not only not tell us how to raise our kids correctly, it will, in actuality, approbate actions that any sane person would think constitutes morally impermissible methods of child rearing. Thus, quantum mechanics is required. Many of us also frequently engage in behavior that yields some sort of environmental pollution. Will the NAP (Euclidean geometry) gives us the right answer as to what we ought to do? Again, no. It will tell us that we cannot, as Zwolinski once again points out, drive an automobile or light a campfire, conclusions that are surely absurd. Thus, non-Euclidean geometry is required. Several people are confronted every day with the chance to commit some kind of fraud to make a quick buck or reap some benefit. Will the NAP tell these individuals how they ought to act? As Zwolinski shows, it will not. Our high school physics and mathematics has failed; we need a more sophisticated theory.

Since the adoption of the NAP results in rocket scientists trying to make their way with Newtonian mechanics, we need to beef up the NAP, rendering it capable of handling the sorts of problems we as rocket-scientist-like practical agents face. In editing the NAP, there seems to me to be two paths we can take. First, we can radically alter or add to our definition of “aggression,” in hopes of reproaching the sorts of actions our original NAP failed to delimit as off-limits. Kuznicki offers an attempt at doing this in hopes of rendering fraud impermissible; namely, he advocates we classify as morally impermissible actions that are “impediments to reflective self-rule” to go along with our ban on brute physical aggression. This may work, but it is certainly not enough. What do we add to physical aggression and impediments to self-rule if we are to outlaw a parent starving their child? What do we add to allow for reasonable amounts but not too much pollution? Moreover, we also run the risk of our amendments yielding results we find unacceptable. Would my neighbor playing loud heavy metal music several hours throughout the day impede my ability to reflectively self-rule? Maybe, if it sufficiently hindered my concentration. Yet most libertarians would find it acceptable to do something on one’s property as benign as playing loud music. So now we need to further edit what is meant by “reflective self-rule” to account for this result. Epicycles upon epicycles.

The second way we can strengthen the NAP proceeds as follows: we can keep our original understanding of what constitutes aggression, but then add a list of exemptions we consider to be legitimate instances of when the NAP may be transgressed. We then get something like this: it is morally obligatory to follow the dictates of the NAP except in cases x­₁, x_2­, x₃,…, x_n, in which case it is morally permissible (or perhaps obligatory) to disobey the dictates of the NAP_­. The problem, though, remains that variable n can be a high – indeed very high – number, to the point at which listing all exemptions becomes difficult, if not impossible. In fact, there is probably a case to be made that, given the tremendously narrow scope of the NAP and the ingenious ability of philosophers to dream up counterfactuals, the list of exemptions might be un-codifiable, presenting a problem for this approach to amending the NAP. Instead, it might be argued that rather than listing each and every exemption to the principle, we might simply develop a secondary rule determining when some situation constitutes a legitimate instance of when the NAP may be permissibly violated. But this project also seems rather hopeless, for any rule that concretely adjudicates exemptions from non-exemptions will have to contain excruciating detail – perhaps an un-enumerable amount of detail (we could not, for example, simply say that situation s constitutes an instance permitting exemption from the dictates of the NAP just in case situation s yields a severe reduction in an agent’s autonomy, because it is not clear what constitutes a “severe reduction in an agent’s autonomy”). Once again, epicycles upon epicycles.

It is not the case that every ethical system yielding implausible implications through counterfactual analysis must be abandoned for another ethical system. It might be that an ethical theory is polished to the point that it can be revised to such a miniscule extent that it remains worth holding on to – after all, one or two epicycles does not grossly detract from the elegance of an otherwise perfectly elliptical orbital path. But there comes a point when the amount of revision borders on the absurd – after we have drawn the fifteenth, sixteenth, seventeenth epicycle. At this point, it makes sense to start anew in hopes of developing a better theory that does not require such extensive revision, allowing for maintained elegance. I think the NAP is in this latter category. As such, it is high time we, as libertarians, do as Zwolinski bids by undergoing our own Copernican Revolution in search of a better moral and political philosophy.

During his recent diatribe against libertarians Bill Maher said, “Libertarians also hate Medicare and Social Security and there are problems with those programs but here’s the thing: It beats stepping over lepers and watching human skeletons shit in the river and I also like not seeing those things.”

Libertarians hear this sort of thing a lot. “You don’t think there should be limits on campaign spending? Then you must want corporations to buy elections!” Or, “You’re opposed to public schooling? What, you think all our children should just stay ignorant?”

We call this a false dilemma, a well-known logical fallacy. A person commits it when he limits the available choices in an argument too much. You can pick between A or B, he says, when in fact there’s an option C (and D, E, and F), as well. For Maher, either we keep Medicare and Society Security or we allow horrific poverty.

The false dilemma’s a logical fallacy for good reason and so by itself is never a good argument against, well, anything. But that doesn’t mean we should just ignore it. Instead, once we’ve noticed how many people employ false dilemmas against libertarian proposals, we should take a moment to ask why.

I submit that the false dilemma’s prevalence results in part from the way many libertarians talk about, and argue for, their political views.

If you have no reason to think options exist beyond just A and B, then if you hear someone arguing strongly against A, it’s not stupid to assume he’s either in favor of B or at least prefers B to A. So if you aren’t aware of any ways to prevent destitution besides Social Security, and you hear a libertarian arguing strongly against the morality of Society Security, then it’s rather likely you’ll conclude that he either wants destitution for the poor or at least would rather see the poor destitute than suffer the moral harm of Social Security.

Libertarians bear some of the blame for this. Quite often when choosing our rhetoric, we have a tendency to focus on “not A” instead of saying, “B’s not good either, so let’s instead do C.” For example, folks on the left are less likely to attack us with false dilemmas if we focus not so exclusively on the rights violations inherent in paying for Social Security, but instead point out that Social Security doesn’t work all that well or efficiently if the goal is to prevent destitution, and then offer better alternatives.

This “not A” tendency could result from the simple fact that offering alternatives means having persuasive alternatives in mind. And while they’re myriad, not all of us have the time or inclination to learn them. Call it a kind of rational ignorance in political debate. Far easier to just apply a single principle, a “universal acid” as Daniel Dennett calls it.

But we’re often also motivated by a desire to maintain our principles. Principles are good, of course. That libertarians say we value freedom and mean it is a crucial difference between us and conservatives and progressives. On the other hand, we need to recognize that non-libertarians don’t accept our core principles. If they did, they wouldn’t be non-libertarians. So if our goal is not just to be right, but to be persuasive, then starting with common ground can be rather more effective. Yes, we take a principled stand against the state coercion behind Social Security, but we also don’t want people to suffer from rampant poverty. In fact, much of what’s appealing about libertarianism is that it’s a genuine path to both: we can be free and prosperous. We shouldn’t water down our libertarianism but we should pay attention to when leading with the argument from prosperity—and using it as a way to then persuade on the issue of freedom—can be more effective than making only the argument from freedom.

Bill Maher’s fulmination just shows that the way we express our ideas is often as important for their persuasiveness as the ideas themselves.

Jason Kuznicki makes a game attempt to salvage the “Non-Aggression Principle” from Matt Zwolinski’s six-pronged assault, essentially arguing that the NAP is something like Euclidian geometry or high school physics—a simplified model that may be, strictly speaking, false in its pure form, but serves as a good enough rough rule for most circumstances. And this may seem promising if we think about other moral principles and rules about which something similar can be said. Parents typically teach their children that one ought always to tell the truth, but most will acknowledge that there are many exceptions—cases where some degree of deviation from the general rule is either permissible (to spare someone’s feelings or protect a confidence, if the subject is trivial) or even obligatory (the canonical “murderer at the door” asking where his prospective victim may be found). I doubt this will work for the NAP, however, for several reasons.

First, the viability of a principle has to be judged in the context of what role it is meant to be playing in your ethical thinking. If the NAP is understood as akin to “tell the truth”—one among many rules of thumb that establish rebuttable presumptions for guiding your daily conduct—then it is perfectly servicable. May I respond to an insulting remark by throwing a punch? I may not. But that is not really how libertarians usually want to use the NAP: Rather, it is meant to serve as a kind of master principle from which other more concrete rules may be derived, and against which competing forms of social order may be evaluated. And for that purpose it is not particularly useful. When we are not looking for rough guides to our day-to-day conduct, but engaged in the rather more leisurely activity of theory-building, there is less practical reason to rely on simplified models because “the math is easier,” and more to the point, we are most likely to be wrestling with precisely the kind of hard cases that arguably constitute exceptions to the rough rule, or deciding between variant forms of the very concepts on which the NAP relies.

If the NAP were truly a universal, exceptionless master principle—if the apparent counterexamples were either bullets we could bite or cases where the principle would yield the right answer after all once properly understood—then we could employ it directly even at the highest theoretical level. But if, as Jason seems to concede, we are allowing that the exceptions are really exceptions, then we are implicitly relying on some other higher-level principles—respect for autonomy or hedonic utility or Kantian universalization or contractualist agreement—to limn the boundaries. But at the theory building level, the appropriate thing to do is to refer directly to those deeper principles. To extend the initial metaphor, it is precisely when you are trying to do fundamental physics that you end up needing to step back from the approximate truths of classical mechanics. The NAP is no help deciding the questions you’re attempting to answer at this level, because as Zwolinski notes, it’s parasitic on theories of property and coercion that reside at this same level of abstraction. You can’t resolve a philosophical debate between a classical liberal and a socialist by appealing to the NAP, because each can claim their view is consistent with that principle given their theories of property: The state is not “aggressing” on an individual “property owner” if in fact The People ultimately own (or have some kind of share right in) all property, given the normatively loaded way “aggression” is used here. The appeal of the NAP lies in its apparent simplicity and intuitive plausibility (tautologies tend to be intuitively plausible), but it’s typically deployed in a way that amounts to a kind of shell game: I argue that socialism must be rejected on the grounds that it violates this one simple moral principle, and hope my interlocutor doesn’t notice that I’ve essentially begged the question by baking a theory of strong property rights incompatible with socialism into my conception of “aggression,” when of course libertarian property rights are ultimately backed by the threat of (individual or state) violence as well.   

This gets us to the deeper problem with the Non-Aggression Principle: It is not really a principle at all, but a tautology gesturing in the direction of a theory. Suppose I tell you that I have, at long last, discovered the simple principle from which all morality derives. Assuming you suppress your initial skepticism about this bold claim, you are likely to be disappointed if I then reveal that my principle is something like “One ought not to commit wrong actions,” or “Never violate the rights of others.” The latter is not completely content free—it specifies that it is the moral claims of individuals that matter, rather than compliance with some natural or divine law unmoored from human consequences—but neither principle really gives us the concrete guidance we had expected, even at a highly abstract level: These are formaltruths given the meaning of the normative terms “right,” “wrong,” and “ought,” not substantive guides to which actions or social orders satisfy these conditions. This is slightly less obvious in the case of the NAP because the partly-descriptive term “aggression” seems to add a substantive component. Yet this amounts to little more than the recognition that we are creatures made of matter whose moral entitlements are ultimately guaranteed or made effective by the application or (more often) implicit background threat of physical force in the last resort. A “right” is a claim that you are justified in ultimately resorting to (direct or indirect) force to make effective; whether or not a particular act counts as “aggression” or “initiation” of force depends on whether the right enforced is a genuine one. But all the real action is in the definition of rights; invoking the NAP adds nothing. It is tantamount to saying “only enforce rights that are really rights.” To establish your right over (say) your car just is to establish that I ought not to take or use it without your permission (perhaps barring extraordinary circumstances, the parameters of which will tend to be implicit in the argument establishing the right). It is neither necessary nor illuminating to add the additional premises that taking what you have a right to counts as “aggression,” and that one ought not to aggress.

Now, it is surely true, as Jason suggests, that any simple principle is going to be highly incomplete and tied to a larger theoretical apparatus. The utilitarian principle of “the greatest good for the greatest number” does not tell us whether to maximize aggregate or average utility, or whether to concieve of utility in purely hedonic and subjective terms, as a measure of preference satisfaction, or something else. The Rawlsian Difference Principle, which stipulates that social inequalities are justified only to the extent they benefit the worst off group in society, does not in itself tell us how to understand “worst off”: For Rawls, it is determined by a laundry list of “primary goods,” but one could just as easily apply a variant difference principle that used hedonic utility instead. The Millian Harm Principle—individuals may be restrained only to prevent harms to others, not to themselves—notoriously runs into a thicket when we try to specify precisely what counts as a “harm.” It is no objection to a principle that it depends on theory. But it is an objection if the principle is being made to do load-bearing work—treated as a fundamental “axiom” rather than a presumptive rule derived from higher-order principles—that conceals those dependencies. The utilitarian principle—though “gappy” and therefore susceptible to a wide array of variant interpretations—really is “axiomatic” in some sense: The basic idea that one ought to weigh the interests of all equally—and then act in the way that (or follow the rule that) generates the greatest net of benefits minus burdens—really is fundamental in utilitarian theory. It is not quite that there is nothing further to say about why it might be plausible or not, but we are pretty close to the core intuition at the heart of any moral theory that one ultimately either shares or doesn’t. The Harms Principle and Difference Principle, by contrast, are transparently derivative rules, the upshot or result of a lengthy preceding argument in light of which they are to be interpreted, fleshed out, and applied to particular circumstances.

The NAP as deployed in much libertarian rhetoric tends to trade on an ambiguity between these two types: It often masquerades as the former, even though it only really has content if understood as the latter. We then often end up being misled into thinking we can defend a particular form of sociopolitical order just by appealing to the simple and intuitively plausible NAP, without noticing that the highly intuitive formal NAP only gets substantive content by choosing a specific cluster of contestable conceptions of “aggression,” “property,” “coercion,” “consent,” and so on. Yet the choice between these conceptions ultimately just is the choice between competing sociopolitical orders—so arguments of this form are circular.

None of this is to deny that the NAP may be a perfectly servicable way to sum up what libertarianism is all about to the fellow on the next stool at the bar who’s never heard of it. But if we are doing political philosophy, we are probably better off leaving it behind: It is a principle that does no independent work, but tends to muddy the waters by appearing to. If we are interested in building sound theories, rather than winning quick debates against inattentive opponents, we should hope to do more than that.

Matt Zwolinski says we should scrap the non-aggression principle: It gives easy answers in some places, but it stumbles in others. Better to just replace it, he argues:

[T]he NAP’s plausibility is superficial. It is, of course, common sense to think that aggression is a bad thing. But it is far from common sense to think that its badness is absolute, such that the wrongness of aggression always trumps any other possible consideration of justice or political morality. There is a vast difference between a strong but defeasible presumption against the justice of aggression, and an absolute, universal prohibition. As Bryan Caplan has said, if you can’t think of counterexamples to the latter, you’re not trying hard enough.

My sense is that both Zwolinski and Murray Rothbard, the NAP’s key exponent, may be asking too much of their models. Rothbard for his part doesn’t seem to notice when the model isn’t delivering. That’s why he gives what are in my view some unconscionable recommendations about children. Zwolinski is right to reject them:

It’s one thing to say that aggression against others is wrong. It’s quite another to say that it’s the only thing that’s wrong – or the only wrong that is properly subject to prevention or rectification by force. But taken to its consistent extreme, as Murray Rothbard took it, the NAP implies that there is nothing wrong with allowing your three year-old son to starve to death, so long as you do not forcibly prevent him from obtaining food on his own. Or, at least, it implies that it would be wrong for others to, say, trespass on your property in order to give the child you’re deliberately starving a piece of bread. This, I think, is a fairly devastating reductio of the view that positive duties may never be coercively enforced. That it was Rothbard himself who presented the reductio, without, apparently, realizing the absurdity into which he had walked, rather boggles the mind.

Partly as a result, Zwolinski seems to think we need to give up on the NAP as well. First he recommends a “defeasible presumption”—probably the right approach, I’d say—but in his conclusion, he seems to aim at something much larger. Though not necessarily better:

Libertarians are ingenious folk. And I have no doubt that, given sufficient time, they can think up a host of ways to tweak, tinker, and contextualize the NAP in a way that makes some progress in dealing with the problems I have raised in this essay. But there comes a point where adding another layer of epicycles to one’s theory seems no longer to be the best way to proceed. There comes a point where what you need is not another refinement to the definition of “aggression” but a radical paradigm shift in which we put aside the idea that non-aggression is the sole, immovable center of the moral universe. Libertarianism needs its own Copernican Revolution.

We are ingenious folk! But it’s not clear we need anything as clever, or large, as a Copernican Revolution.

Since we’re on the subject, let’s talk physics. To model how a billiard ball rolls on a table, one makes simplifying assumptions—the table is a perfectly flat plane, the ball is a perfect sphere, the mass is distributed equally, and the like. One does these things not because the simplified model is perfectly true to life, but for three related reasons: (1) the model is often close enough; (2) the math is vastly easier; and (3) you can use it to say things that are more or less true about billiard balls anywhere: here, in Spokane, and—with only minor adjustments—on Mars.

Moral and political philosophy should be like that. They should make simplifying assumptions. They must, if they are to do anything more than reference isolated cases without any extensive explanatory power. And the ability to extend to additional cases is the very reason we do philosophy, at least as a practical matter.

This is why Michael Huemer’s treatment of the non-aggression axiom seems like a significant step forward to me. To Huemer, the non-aggression principle is not really an axiom at all; it’s a strong but rebuttable presumption. That may seem like a weakening to a lot of folks, but if so they should consider the radicalism of Huemer’s conclusions as evidence that he’s not going weak in the knees.

By contrast, I have to say Zwolinski’s objections sound as if he is indicting libertarianism for saying that the billiard ball was a sphere, while only he knows, sadly, that spheres have nothing to teach us about billiards. Granted, the first was false, but so is the second.

Spheres are a good solid start to the problem, and we ought not to feel too badly about needing refinements from time to time. The word for these refinements is not epicycles, however. It’s engineering.

I think this analogy points the way toward solving many of the conundrums Matt poses in his post. Many of his difficulties, including children, pollution, and the need for a clear definition of property, are all a part of building models that meet particular real-world circumstances. Of course abstract theory has much to tell us. And of course it can’t tell us everything.

In one case, though, I will commend to him a useful solution that doesn’t fit the above. His fourth conundrum holds that fraud is unrelated to force, and that a libertarian society might find itself embarrassingly unable to punish fraud. I disagree.

Fraud is wrong because it, like physical force, defeats the will without convincing the intellect. As such:

[Force and fraud] are both impediments to reflective self-rule, and any political theory that values reflective self-rule is permitted to find them similar problems. This is why both are properly censured in libertarian political thought… While there remain many salient differences between force and fraud, the likeness is not imaginary or arbitrary, at least not any more so than are concepts like “will” and “intellect.”

It’s okay to use force to combat fraud, just as it’s okay to use force to combat a physical aggressor. It may not even be too much to say that both force and fraud are species of some larger genus, albeit one that lacks a name in our language. Both acts attempt to subvert individual atuonomy, and both may therefore be treated alike, at least if we do value individual autonomy as our highest political end.

I’d add that we libertarians are a good deal more consistent than most about the censure here—we wouldn’t make exceptions and allow the initiation of force simply because some people call themselves “the state.” But the intuitions that force and fraud are almost always wrong, and that they are wrong in similar ways, are both very common. They are not at all weird, and, used properly, they constitute a strong argument for our side. They ought not to be rejected.

Many libertarians believe that the whole of their political philosophy can be summed up in a single, simple principle. This principle—the “non-aggression principle” or “non-aggression axiom” (hereafter “NAP”)—holds that aggression against the person or property of others is always wrong, where aggression is defined narrowly in terms of the use or threat of physical violence.

From this principle, many libertarians believe, the rest of libertarianism can be deduced as a matter of mere logic. What is the proper libertarian stance on minimum wage laws? Aggression, and therefore wrong. What about anti-discrimination laws? Aggression, and therefore wrong. Public schools? Same answer. Public roads? Same answer. The libertarian armed with the NAP has little need for the close study of history, sociology, or empirical economics. With a little logic and a lot of faith in this basic axiom of morality, virtually any political problem can be neatly solved from the armchair.

On its face, the NAP’s prohibition of aggression falls nicely in line with common sense. After all, who doesn’t think it’s wrong to steal someone else’s property, to club some innocent person over the head, or to force others to labor for one’s own private benefit? And if it’s wrong for us to do these things as individuals, why would it be any less wrong for us to do it as a group – as a club, a gang, or…a state?

But the NAP’s plausibility is superficial. It is, of course, common sense to think that aggression is a bad thing. But it is far from common sense to think that its badness is absolute, such that the wrongness of aggression always trumps any other possible consideration of justice or political morality. There is a vast difference between a strong but defeasible presumption against the justice of aggression, and an absolute, universal prohibition. As Bryan Caplan has said, if you can’t think of counterexamples to the latter, you’re not trying hard enough. But I’m here to help.

In the remainder of this essay, I want to present six reasons why libertarians should reject the NAP. None of them are original to me. Each is logically independent of the others. Taken together, I think, they make a fairly overwhelming case.

1. Prohibits All Pollution – As I noted in my last post, Rothbard himself recognized that industrial pollution violates the NAP and must therefore be prohibited. But Rothbard did not draw the full implications of his principle. Not just industrial pollution, but personal pollution produced by driving, burning wood in one’s fireplace, smoking, etc., runs afoul of NAP. The NAP implies that all of these activities must be prohibited, no matter how beneficial they may be in other respects, and no matter how essential they our to daily life in the modern industrialized world. And this is deeply implausible.
2. Prohibits Small Harms for Large Benefits – The NAP prohibits all pollution because its prohibition on aggression is absolute. No amount of aggression, no matter how small, is morally permissible. And no amount of offsetting benefits can change this fact. But suppose, to borrow a thought from Hume, that I could prevent the destruction of the whole world by lightly scratching your finger? Or, to take a perhaps more plausible example, suppose that by imposing a very, very small tax on billionaires, I could provide life-saving vaccination for tens of thousands of desperately poor children? Even if we grant that taxation is aggression, and that aggression is generally wrong, is it really so obvious that the relatively minor aggression involved in these examples is wrong, given the tremendous benefit it produces?
3. All-or-Nothing Attitude Toward Risk – The NAP clearly implies that it’s wrong for me to shoot you in the head. But, to borrow an example from David Friedman, what if I merely run the risk of shooting you by putting one bullet in a six-shot revolver, spinning the cylinder, aiming it at your head, and squeezing the trigger? What if it is not one bullet but five? Of course, almost everything we do imposes some risk of harm on innocent persons. We run this risk when we drive on the highway (what if we suffer a heart attack, or become distracted), or when we fly airplanes over populated areas. Most of us think that some of these risks are justifiable, while others are not, and that the difference between them has something to do with the size and likelihood of the risked harm, the importance of the risky activity, and the availability and cost of less risky activities. But considerations like this carry zero weight in the NAP’s absolute prohibition on aggression. That principle seems compatible with only two possible rules: either all risks are permissible (because they are not really aggression until they actually result in a harm), or none are (because they are). And neither of these seems sensible.
4. No Prohibition of Fraud – Libertarians usually say that violence may legitimately be used to prevent either force or fraud. But according to NAP, the only legitimate use of force is to prevent or punish the initiatory use of physical violence by others. And fraud is not physical violence. If I tell you that the painting you want to buy is a genuine Renoir, and it’s not, I have not physically aggressed against you. But if you buy it, find out it’s a fake, and then send the police (or your protective agency) over to my house to get your money back, then you are aggressing against me. So not only does a prohibition on fraud not follow from the NAP, it is not even compatible with it, since the use of force to prohibit fraud itself constitutes the initiation of physical violence.
5. Parasitic on a Theory of Property – Even if the NAP is correct, it cannot serve as a fundamental principle of libertarian ethics, because its meaning and normative force are entirely parasitic on an underlying theory of property. Suppose A is walking across an empty field, when B jumps out of the bushes and clubs A on the head. It certainly looks like B is aggressing against A in this case. But on the libertarian view, whether this is so depends entirely on the relevant property rights – specifically, who owns the field. If it’s B’s field, and A was crossing it without B’s consent, then A was the one who was actually aggressing against B. Thus, “aggression,” on the libertarian view, doesn’t really mean physical violence at all. It means “violation of property rights.” But if this is true, then the NAP’s focus on “aggression” and “violence” is at best superfluous, and at worst misleading. It is the enforcement of property rights, not the prohibition of aggression, that is fundamental to libertarianism.
6. What About the Children??? – It’s one thing to say that aggression against others is wrong. It’s quite another to say that it’s the only thing that’s wrong – or the only wrong that is properly subject to prevention or rectification by force. But taken to its consistent extreme, as Murray Rothbard took it, the NAP implies that there is nothing wrong with allowing your three year-old son to starve to death, so long as you do not forcibly prevent him from obtaining food on his own. Or, at least, it implies that it would be wrong for others to, say, trespass on your property in order to give the child you’re deliberately starving a piece of bread. This, I think, is a fairly devastating reductio of the view that positive duties may never be coercively enforced. That it was Rothbard himself who presented the reductio, without, apparently, realizing the absurdity into which he had walked, rather boggles the mind.

There’s more to be said about each of these, of course. Libertarians haven’t written much about the issue of pollution. But they have been aware of the problem about fraud at least since James Child published his justly famous article in Ethics on the subject in 1994, and both Bryan Caplan and Stephan Kinsella have tried (unsatisfactorily, to my mind) to address it. Similarly, Roderick Long has some characteristically thoughtful and intelligent things to say about the issue of children and positive rights.

Libertarians are ingenious folk. And I have no doubt that, given sufficient time, they can think up a host of ways to tweak, tinker, and contextualize the NAP in a way that makes some progress in dealing with the problems I have raised in this essay. But there comes a point where adding another layer of epicycles to one’s theory seems no longer to be the best way to proceed. There comes a point where what you need is not another refinement to the definition of “aggression” but a radical paradigm shift in which we put aside the idea that non-aggression is the sole, immovable center of the moral universe. Libertarianism needs its own Copernican Revolution.