I had an interesting discussion this morning, with a colleague from across town. The topic was commensuration, a concept that we both have been interested in for some time (actually, our intellectual ‘pedigree’ is fairly similar, and I should say with some amount of grace that I’ve leaned on his insights more than he on mine).
Commensuration is the process by which qualitatively different objects are brought into tension via a common metric. For instance, how do we compare Barnard College, a women’s college in New York City, institutionally affiliated with but distinct from Columbia University, with Spelman College, a historically-Black women’s college, historically affiliated but distinct from Morehouse College in Atlanta? Do we just say that they are different? Well, maybe. But we can compare them along a number of lines: academic reputation, size, what students do when they graduate, region, etc.
When these comparison categories are ordinal, that is, they are meaningfully rank-able, this is what we mean by commensuration. Commensuration draws different qualities into tension and transforms them into quantitative difference. Region may make the schools comparable, but not commensurable; class size, percentage of PhD’s teaching courses, reputation, rank – these make the schools commensurable.
Why does this matter? Commensuration has potentially powerful effects, sometimes transformational ones. More on this later.