In the past week Theresa May has announced a comprehensive review of tuition fees charged by universities. Among the proposals is the idea of setting different fee caps for different types of degree course.

Degrees in the STEM disciplines, which cost more to provide and whose graduates tend to earn higher salaries post-graduation, would be able to command higher fees than those in the Arts, Humanities, and Social Sciences. These plans have been met with strong criticism from within the university sector.

The review is happening because the flat rate of tuition charged by virtually all universities for all degrees is not what the Government envisaged when it raised the cap on tuition fees back in 2012. Then, it was assumed that universities would compete for students by offering lower fees and that few students would end up being charged the maximum rate. Instead, almost all students are charged the maximum, regardless of the institution they attend or the degree course they pursue.

What’s so wrong with demanding higher fees from students whose courses cost more to provide?

On the face of it, the argument that tuition fees should reflect the cost of degree provision seems both logical and fair, especially when these students stand to be higher earners upon graduation.

It’s not difficult to see how a STEM degree could rack up many times the costs of an arts, humanities, or social sciences degree. Laboratory equipment, state-of-the-art computers to run data-analysis applications and field trips are just some of the resources that are required be financed over and above the cost of classroom provisions.

But determining which degrees should command higher and lower fees is more challenging than it might at first appear. Let’s imagine two universities that offer a broadly comparable social sciences degree. Both offer the same hours of classroom teaching and tutorial time and both offer equivalent IT and library resources to support their students. But one of the courses is taught in a teaching-focused institution, mostly by lecturers who have qualified in the past five years. The other one is taught in a leading research-focused institution that employs several world-leading experts in the field. Do the overheads of employing these leading researchers, at wages more than double those of their more junior counterparts, count against the direct costs of degree provision? Does the potential value for students of a dissertation supervised by a global leader in the field permit the institution to charge more?

What about the English department that hosts monthly readings and talks by prizewinning authors? For a student studying literature this kind of enriching environment might be the most important part of their degree experience. But can the university offset the cost of such events by charging higher fees to reflect this?

An ideological shift

Even leaving aside the difficulties of figuring out what should and shouldn’t be factored into the costs of a degree, an ideological battle is being waged. If the government’s proposals were enacted, they would put an end to one of the central beliefs of Higher Education policy in the UK: that a university degree is valuable in its own right, irrespective of what subject it’s in and at which UK institution it was obtained.

While it’s true that employers – and indeed society at large – don’t necessarily buy into this idea, moving away from it is still a big shift to make at the highest policy levels and it could have several unintended consequences. The most obvious consequence, and the one that has gained most immediate publicity, is that making STEM degrees more expensive will simply deter prospective students from taking them.

British students tend to specialise when choosing their A Levels, and it’s unlikely that many will switch from planning to do a Physics degree to doing one in Classics instead. But we could still see students opting for social rather than “hard” sciences. This a big deal given that there’s currently a skills shortage in STEM disciplines.

Conversely, the lower cost of Arts and Social Sciences degrees could end up contributing to a public perception of these degrees as being less valuable than degrees in the sciences. This in turn could have an impact on the prospects of Arts graduates competing against STEM graduates in recruitment programmes open to graduates from multiple disciplines. A measure that’s designed to compensate for the pay gap between Sciences and Arts graduates may therefore end up reinforcing that pay gap by reshaping public perceptions of degree value.

There’s no doubt that high tuition fees and the high levels of debt with which new graduates are leaving university need to be addressed. And the Government isn’t wrong to want to revisit the models by which fees are assessed. But it should be careful about creating hierarchies of degrees, or even a two-tier system – that devalues some programmes and places an expensive premium on others.