Western countries will adopt (or consider adopting) state-mandated “medical passports”—so-called green passes—meant to prevent covid-19’s spread. They will compel private individuals to carry such passports if they want access to certain facilities or events (restaurants, theaters, concert arenas, etc.), I often hear libertarians—or people just sympathetic to libertarianism—supporting such state interventions with the following argument: “The green pass is compatible with libertarianism, because it directly stems from the nonaggression principle; in fact, if you do not have the green pass—and hence are (potentially) infectious—by infecting other people, you would be aggressing against them.”
My point is not so much that “infection” does not necessarily equate to “aggression,” but that when it comes to airborne communicable diseases, the simple fact of two people—A and B—agreeing to occupy the same room (or any kind of physical space where it is physically impossible for them not to breathe the same air) is sufficient to rule out the possibility of aggression. I think failing to understand this argument reveals a deep misunderstanding of what libertarianism is about—property rights and nonaggression.
My argument is twofold. First, I will briefly define what I believe libertarianism to be about. Second, by consistently applying the notions of “property” and “aggression,” I will argue the following: if A and B agreed to share a physical space wherein it is physically impossible for the two of them not to breathe the same air, then it would make no sense to classify A infecting B (or vice versa) as aggression.
Libertarianism, Aggression, and Property Rights1
What, in short, is libertarianism? It is that political philosophy concerned with 1) establishing rational and just principles—derived from human nature—for resolving human conflicts over scarce resources and 2) defining the boundaries of property rights and aggression.
Rothbard summarized the first part of the definition perfectly when he wrote that the core of libertarianism is
to establish the absolute right to private property of every man: first, in his own body, and second, in the previously unused natural resources which he first transforms by his labor. These two axioms, the right of self-ownership and the right to “homestead,” establish the complete set of principles of the libertarian system. The entire libertarian doctrine then becomes the spinning out and the application of all the implications of this central doctrine.2
When it comes to the second part of the definition, the right to property can be defined as the right of the owner to employ and enjoy his own property to whatever extent he deems fit—hence, doing with what he owns (whether a physical object or his own physical body) whatever he would like to do. Symmetrically, aggression is the denial of the right to property; that is, aggression—or invasion—occurs whenever there is interference with the owner’s use or enjoyment of his own property.3
Therefore, if we establish that in a given scenario A and B are using and enjoying their own bodies and physical property to the extent they deem fit, then we can safely rule out any possibility of aggression occurring through their interaction. On the contrary, we should conclude that a third party—be it C, the collectivity, or the state—interfering with their use and enjoyment of their own property would be invading A’s and B’s rights, thus aggressing against them.
Infection, Air Ownership, and Contracts
Now, having established our libertarian framework, the question is: Under which circumstances, if any, does infection equate to aggression?
Let’s draw up a first scenario. Let’s assume A and B decide to dine at C’s restaurant, both knowing that the latter does not require his clients to prove, via “green pass,” that they are not carrying a particular airborne disease, say covid. Assume, also, that the physical space A and B will occupy while dining is such that it is physically impossible for the two of them not to breathe the same air—that is, A would end up breathing in the air that B breathed out, and vice versa. Lastly, let’s assume that A carries the airborne disease and infects B. Now the question is: Did A aggress against B?
The perspective I offer is no, he did not. Why? Our (libertarian) answer can be found by analyzing the property rights involved in this situation—and asking if any property right has been infringed upon.
We can schematize the circumstances as follows: A and B signed a contract with C, a contract which implicitly stipulated that the two of them would have to share the same physical space and breathe the same air. Therefore, they agreed to place their own bodies in a potentially infectious environment—because airborne communicable diseases are transmitted through the air. Hence, B could not claim to have been aggressed against by A: B could not maintain that A interfered in any way with his right to enjoy his own property, including his physical body, to the extent he deemed fit. And neither could B sue C (the restaurant’s owner) for aggression: in fact, since a condition of the that contract B signed with C was that A and B would be breathing the same air, B’s decision to dine in C’s restaurant must be construed as acceptance of such terms and conditions of service.
However, I also want to stress what I am not claiming; that is, if B accepts a risk involved in a transaction or an interaction with A and suffers damages in consequence, I do not claim that B’s acceptance of such risk is sufficient to rule out the possibility that he suffered aggression.
Take for instance a second scenario: B buys some meat from A, and this meat turns out to be spoiled and gives B food poisoning. Even if it is true that buying meat involves the physical possibility of such meat being spoiled, it is also true that this need not be the case and can be prevented by A. In other words, while it is impossible for A and B not to breathe the same air if they are close enough in physical space, it is not impossible for B to buy some wholesome, unspoiled meat from A. The contract between A and B featuring an exchange of money for meat does not necessarily imply that a share (if we reason in terms of expected value and risk) of such meat will be spoiled, whereas the abovementioned contract featuring A, B, and C (the restaurant’s owner) does involve A and B being close enough in physical space and hence breathing the same air!
So, infection does equate to aggression if and only if A violates B’s use and enjoyment of his legitimately acquired property; however, as we have seen, this need not be the case—we can think of instances of A infecting B without interfering with the latter’s property rights. Therefore, infection does not equate aggression when A infects B (or vice versa) as a consequence of the two of them using and employing their own property as they deem fit—for instance, entering into the abovementioned contract with the restaurant’s owner, C.
To me, it does not matter how “pragmatic” and “willing to compromise” you feel inclined to be: if you favor government interference with private individuals’ desire to freely associate—that is, government aggression—then you cannot define yourself a libertarian, and, as (I hope) have shown, this holds true when we talk about infections and pandemics as well.
1. This section obviously largely draws upon the writings of Murray N. Rothbard and Hans-Hermann Hoppe. In particular, see Rothbard, The Ethics of Liberty (New York: New York University Press, 1998), chap. 15, and Rothbard, Man, Economy, and State, with Power and Market,” 2d scholar’s ed. (Auburn, AL: Ludwig von Mises Institute, 2009), chap. 6, section 16.
2. Murray N. Rothbard, For a New Liberty: The Libertarian Manifesto, 2d ed. (Auburn, AL: Ludwig von Mises Institute, 2006), pp. 47–48.
3. Cf. Murray N. Rothbard, Economic Controversies (Auburn, AL: Ludwig von Mises Institute, 2011), pp. 396–98.