Migrants, en route to the United States, make their way to San Pedro Tapanatepec from Mexico, October 27, 2018. (Ueslei Marcelino/Reuters)

“Open borders” is a phrase that is thrown around as an accusation — anybody who is marginally less restrictive on immigration than the speaker would like him to be is described as advocating “open borders.” In reality, there are very few open-borders voices in our political discourse. Some people are more restrictive (Mark Krikorian et al.), some people are less restrictive (a preference frequently voiced in the opinion pages of the Wall Street Journal), and a few take a mixed view (e.g., my own preference would be to make it relatively easy for wealthy and high-earning people to immigrate to the United States and much more difficult for poor and unskilled people). There are precedents for open borders: Victorian England, for one, and the United States, once upon a time, but few people are for that in the current context.

Bryan Caplan, a professor of economics at George Mason University, is one of those who do advocate open borders, and he makes a case for the policy in his new, straightforwardly titled book, Open Borders: The Science and Ethics of Immigration. Professor Caplan is an intelligent and provocative thinker and writer, and I have never failed to find something valuable in his books and essays, especially when I disagree with him.

Professor Caplan’s book is probably not what you are expecting. He is an economist and writes with an economist’s eye. Those of us who are engaged in the business of publishing opinions are used to having our views caricatured and presented in cartoon form (Ahem!) but Professor Caplan has here beaten the critics to the punch, in a sense: Open Borders is a comic book, produced in partnership with “Saturday Morning Breakfast Cereal” artist Zach Weinersmith. Professor Caplan himself appears as a cartoon character, looking a little bit like a bespectacled Waldo in a grey suit. We also get cartoon versions of Donald Trump, J. S. Mill,  John Rawls, Robert Nozick, Voltaire, Richard Posner, Harriet Tubman, Carl Gauss, Milton Friedman, Lee Kuan Yew, Immanuel Kant, Amy Chua, V. I. Lenin, and Jesus.

It may be churlish to describe a comic book as being oversimplified, but there are many instances in which Professor Caplan’s arguments do not even address fairly obvious counterarguments. For example, he notes that unskilled workers who migrate from poor countries to rich countries make ten times as much money for the same work, but does not make a very persuasive argument that with immigration on the scale he is here considering (hundreds of millions to the United States alone) the labor markets of the rich world still will produce comparable results. He describes immigration controls as “global apartheid” and argues that immigration controls are the moral equivalent of Nazi laws restricting where Jews could live and work, a variation on the Berlin Wall, etc.,  which is rhetorically incontinent in the familiar High Libertarian mode. Estimates that open borders would double world economic output are, let us say, highly theoretical.

So, I’m not sold. But Professor Caplan’s argument is multifaceted, energetically presented, fun to read, and worth giving some real attention to if only as an exercise in clarifying one’s own thinking about the question.

Professor Caplan also is the author of several other interesting books, among them Selfish Reasons to Have More Kids. So when it comes to people, he is a more-is-more kind of a guy.