One of the more offbeat arguments against open borders is that open borders, both by increasing prosperity and by the movement of people into countries and cultures with more consumption of meat (particularly factory farmed meat) will increase the overall global consumption of meat (particularly factory farmed meat).

The consequent increase in factory farming will lead to an increase in animal suffering and a decline in animal welfare, making open borders welfare-reducing and/or liberty-reducing for the animal kingdom as a whole.

The argument has three steps:

1. Open borders increases meat consumption (particularly through factory farming) worldwide.
2. This increased meat consumption and factory farming lead to one or more of these: (a) increased human-caused animal suffering, (b) increased overall animal suffering, (c) violation of animals’ natural rights.
3. If we put a nontrivial weight on the flourishing, suffering or rights violations experienced by animals, even if that weight is less than the weight we put per capita on the flourishing, suffering, or rights violations experienced by humans, this could still make open borders bad on net.

We discuss three versions of the argument.

The negative utilitarian or suffering minimization version

Negative utilitarianism (sometimes abbreviated NU) is the view that the value of an action is determined how little pain and suffering it causes. In other words, the goal should be to minimize suffering. The Stanford Encyclopedia of Philosophy has the following summary of negative utilitarianism in its page on consequentialism:

Classic utilitarianism focuses on total utility, so it seems to imply that this government should not provide free contraceptives. That seems implausible to many utilitarians. To avoid this result, some utilitarians claim that an act is morally wrong if and only if its consequences contain more pain (or other disvalues) than an alternative, regardless of positive values. This negative utilitarianism implies that the government should provide contraceptives, since that program reduces pain (and other disvalues), even though it also decreases total net pleasure (or good). Unfortunately, negative utilitarianism also seems to imply that the government should painlessly kill everyone it can, since dead people feel no pain (and have no false beliefs, diseases, or disabilities – though killing them does cause loss of ability) (cf. R.N. Smart 1958).

Negative utilitarianism is not a view widely held at any time among mainstream philosophers. An article by Toby Ord explains why he is not a negative utilitarian.

In the animal welfare context, the negative utilitarian argument against open borders would proceed as follows:

1. Open borders increases meat consumption (particularly through factory farming) worldwide.
2. This increased meat consumption and factory farming lead to increased animal suffering. Note that the claim is not that the net utility of animals goes down, but rather, that the absolute magnitude of animal suffering goes up.
3. If we put a nontrivial weight on the suffering of animals in our negative utilitarian calculus, this is a good argument to reject open borders, even if open borders can alleviate some human misery (perhaps through eliminating or dramatically reducing starvation, malnutrition, and debilitating diseases).

Typical arguments to this include:

• Challenges to the claim that animal suffering in factory farms is more than animal suffering in the wild. Animals in the wild suffer in a number of ways, including much more stress about being killed by predators, not being sure whether they will get enough food to make ends meet, etc. — concerns that are not so pressing in factory farms.
• Challenges to the framework of negative utilitarianism which gives primacy to the minimization of suffering, ignoring the positive utility experienced by animals by living.
• Challenges to the claim that animal suffering should matter at all in cost-benefit analyses.

The utilitarian version: lives not worth living

The utilitarian version puts focus on whether the overall lives of animals that live in factory farms are lives “worth living” — whether the positive utility that emerges from such lives outweighs the pain, suffering, and the inability to live in their natural habitat. In addition, it may also consider whether increased factory farming displaces natural habitats where other animals may have lived lives in natural free-range conditions. The argument would proceed as follows:

1. Open borders increases meat consumption (particularly through factory farming) worldwide.
2. This increased meat consumption and factory farming lead to the creation of animal lives that are not lives worth living when we consider the pluses and minuses of their lives. This type of argument has been made, for instance, in the paper Human Diets and Animal Welfare: The Illogic of the Larder by Matheny and Chan.
3. If we put a nontrivial weight on the overall negative utility of the animal lives created, this outweighs the utilitarian gains to humans from open borders.

Criticisms of this argument arrive from many directions:

• Challenges to the claim that animal lives in factory lives are not worth living, or even that they are worse than the lives of wild animals. Robin Hanson wrote an article defending animal farming where he made this argument:
  

  But the alternative to those future animal lives cut short by butchery is not longer future animal lives. The alternative is that those animals will never have existed. People who buy less meat don’t really spend less money on food overall, they mainly just spend more money on other non-meat food. This results in fewer pig farms and more asparagus farms, and pretty much the same overall amount of land devoted to farming. Creating more asparagus farms does not create more wilderness where wild animals can range free; this is not what asparagus farms do. So the real choice here is between creating pigs who live for a while and then are killed, and creating more asparagus plants.

  If asparagus plants have little moral worth per se, our question then comes down to this: is it good or bad to create pigs who live for a while and then die? Well, is it good to create people that will eventually die? We usually say yes, if their lives are “worth living” overall. That is, if they get value out of being alive, and are not in a situation like severe torture, where they would rather be dead than alive. So are pigs lives worth living?

  We might well agree that wild pigs have lives more worth living, per day at least, just as humans may be happier in the wild instead of fighting traffic to work in a cubical all day. But even these human lives are worth living, and it is my judgment that most farm animal’s lives are worth living too. Most farm animals prefer living to dying; they do not want to commit suicide.

  For a criticism of Hanson’s style of reasoning, see the paper Human Diets and Animal Welfare: The Illogic of the Larder by Matheny and Chan (also linked above).

• Challenges to the inclusion of animal welfare in utilitarian cost-benefit analyses.

The natural right argument

There are different versions of this argument. The strict libertarian natural rights argument asserts that animals have certain natural rights against humans, including the right not to be kept in captivity and the right not to be killed or tortured through coercive or deceptive means. This argument does not require that animals be accorded the same range of natural rights as humans. Humans’ greater cognitive capacities, including the capacity to remember the past and plan for the future, mean that there may be actions that would constitute rights violations for humans but such that comparable actions do not constitute rights violations for animals.

1. Open borders increases meat consumption (particularly through factory farming) worldwide.
2. This increased meat consumption and factory farming lead to increased rights violations by humans against animals.
3. If we put a nontrivial weight on rights violations against animals, this may make open borders a bad deal overall.

There are many counterarguments:

• Animals violate each other’s natural rights all the time (for instance, by preying upon and killing each other). A natural question is whether we should be concerned only about animal rights violations by humans or animal rights violations by all animals. One argument is that while animals do have natural rights, they are not moral agents, so their actions do not constitute rights violations. Nonetheless, a human who facilitates or encourages one animal to kill one another may be engaging in a rights violation.
• More related counterarguments.

Interaction with the expanding circle argument

Open borders advocates have often framed open borders as the next frontier in an expanding circle of moral concern. On the other hand, animal rights advocates have framed concern for animal rights as another potential expansion of the circle of moral concern. Insofar as open borders advocates are blase about the impact of open borders on animal welfare, they could be accused of hypocrisy in terms of acting morally sanctimonious and superior about expanding the circle of moral concern in a specific direction while ignoring and even actively sabotaging other potential directions of expansion.