This is a response to this, which is in turn a response to this and this, which was a response to this, which was a comment on this old E-Lab post of mine. This is old, well-covered ground, so I'll be as brief as I may.
- "Education, in brief, is a public good." This is incorrect. Education does not satisfy the criteria of what it means to be a public good. To be sure, there are positive spillovers: for example, university-educated people generally earn more, and so pay more in taxes. This is why I have no problem with the notion of a partial tuition subsidy. But most of the gains to PSE - monetary and non-monetary - are captured by the student. See here for more on this point, and see here for Frances Woolley's "Why public goods are a pedagogical bad."
- Tuition is not the only cost of PSE. Implicit throughout the post is the presumption that if tuition were free, the university wouldn't cost anything, and all potential students would be on an equal footing. This too is incorrect. The opportunity cost of PSE also includes the wages foregone by the student. This sacrifice is larger than tuition; depending on your circumstance, tuition accounts for roughly one-third to one-quarter of the total cost of a university education. Bringing tuition down to zero does not make university 'free.'
- "Gordon appears to assume that the current demographic snapshot of university students is fixed." No. The stated goal is to change those demographics; the debate is about how to best achieve that goal. The claim that a policy in which 90% of spending consists of giving free money to people who are already going to university will somehow change those demographics requires more evidence than a flat assertion.
- Concerns about student debt. Most graduates either do not have student debt or are able to pay it off without undue inconvenience. It doesn't make a lot of sense to reduce tuition for everyone in order to address the problems of a small minority. To the extent that government action is necessary, it should be a targeted to those who need it.
- The European example of free tuition. There is no evidence that I'm aware of that suggests that this model has a measurable effect on access to university.
- Universality. I don't see how or why the notion of univerality should be endowed with a moral weight comparable to that of vertical equity (redistribution of wealth). Universality is a compromise, the price that progressives are sometimes willing to pay in order to implement a watered-down version of a their preferred, more strongly progressive policy. This compromise may be for political economy reasons (redistributing the gains farther up the income distribution to ensure the support of the median voter) or to reduce administrative costs. I'm not aware of a convincing argument in which the universal nature of a program justifies directing public funds to the top half of the income distrubution.
There are other points, but that's enough for now.