Public good is an economic term with a narrow definition. To qualify as a public good, a good must be both nonexcludable and nonrivalrous. A nonexcludablegood is one which the provider cannot charge consumers for, such as public sidewalks. A nonrivalrous good can be enjoyed by many consumers at once, with an additional consumer’s entry not affecting the degree to which other consumers can enjoy the good (think software or music downloads).

The classic example of a public good is national defense. The U.S. military does not protect me any worse simply because it protects you at the same time. And as long as I live in America, the military protects me whether I pay for it or not.

Other examples of public goods include lighthouses, radio stations, and (my personal favorite) asteroid deflection programs. But higher education is unambiguously not a public good. It is excludable, since universities can force students to pay tuition before receiving an education. It may be nonrivalrous at the margin, since one or two additional students in a lecture hall don’t make much of a difference. But at scale, the number of students in a class has a significant impact on the quality of education (at least at traditional brick-and-mortar colleges).

This definition of public good is widely accepted. And yet, people—including experts in the field, who should know better—constantly fall into the trap of labeling higher education a public good.

What many of these individuals likely mean when they call higher education a public good is that higher education has positive externalities. A positive externality occurs when a good benefits society at large in addition to the good’s consumer. As the argument runs, people who earn college degrees increase their own earnings, but earning those degrees also has beneficial impacts on other people.

Read the source article at aei.org