Moral case from three meta-ethical frameworks
- Libertarian case: There is a natural right to migrate. It is not morally permissible to restrict this right except if there is high certainty of very bad consequences.
- Utilitarian case: Free immigration would increase world GDP by 50-150%, with the majority of the gains accruing to those currently among the world’s poorest.
- Egalitarian case: Free immigration would reduce absolute poverty dramatically, move humanity closer to the ideal of equal opportunity, and end global apartheid. See also the Rawlsian case.
Moral case from other hybrid and practical frameworks
- Bleeding-heart libertarian case, which combines the libertarian case with smatterings of utilitarianism and egalitarianism.
- Conservative and small-government case, which takes a skeptical attitude toward governments trying to exert fine-tuned control over who gets to immigrate.
- Human capabilities case, which argues for open borders within the human capabilities framework developed by Amartya Sen and Martha Nussbaum.
Generalized universalist arguments
Confirmation bias? How do the libertarian, utilitarian, and egalitarian arguments all line up in the same direction?
Skeptics would be quick to point out how convenient it is that arguments from three completely different sets of moral premises: libertarian (predicated on natural rights), utilitarian/consequentialist, and egalitarian, all seem to point toward a similar conclusion. They might suspect that this is an example of confirmation bias at work. After all, in almost all day-to-day debates, the three philosophies give differing conclusions. How, then, this coincidence?
The answer is as follows. Yes, at the margin, there are interesting cases where these differing philosophies give differing answers. Most day-to-day political debates are focused on these margins. Further, interesting philosophical dilemmas and hypotheticals, such as trolley problems, are deliberately chosen to pit different moral philosophies against one another.
But when there is a massive violation of liberty, it is quite likely to be bad from both a utilitarian and an egalitarian perspective. Immigration restrictions are a massive violation of liberty (see the libertarian case) both in principle and quantitatively — large numbers of people who wish to move to another country are prevented from doing so by restrictive immigration policies. Another way of putting it is that immigration restrictions are a massive barrier to the free flow of labor, creating a place premium and preventing labor market convergence. As neoclassical economics would suggest, massive (as opposed to moderate) interventions in markets almost always have bad consequences in terms of utility and equality/fairness.