Well that was a bit of a gap. I apologise for that, as usual!
Plotinus: I noticed you've done a few posts on the heresies of the late Roman Empire: quite by chance, I came across some reading on those the other week. There seems to be quite a lot of disagreement about how far the theology 'mattered' versus other issues that were at stake - in the book I was reading, for example, the author argued that the Donatists were 'really' looking for African independence (or at least to assert themselves as proud Africans) and using the arguments about the place of baptism and the legitimacy of a certain set of bishops as convenient ideas to rally around. As a theologian, I'd be interested in your take on the matter - how far do you think most of the people engaged in theological controversies at the time were really talking about theology? More broadly, I suppose, do you generally take religious arguments at 'face value', or look for something working underneath them?
This is a very complex question that's really impossible to answer with any sureness, because it involves reading between the lines and guessing at people's motives. My instinct is to think that when people make interpretations of the kind you mention - where supposedly theological disagreements are really about politics - they are being anachronistic and failing to appreciate how differently people in the past thought. It's easy for us to understand why the Donatists might have cared about African nationalism (or something like that) - it's not easy for us to understand why they might have cared about who got ordained by which bishops and what that meant about ecclesiastical purity. But that's because we're modern secular people.
Another classic example is the dispute between Cyril of Alexandria and Nestorius, which is often held up as an example of a political dispute masquerading as a theological one. But while there certainly were political and personal elements to this (both of them strike me as quite unpleasant people), that doesn't mean that there weren't genuine theological differences at stake, which these people took very seriously. Contrast that to the dispute a generation earlier between Theophilus of Alexandria and John Chrysostom, where supposed theological differences about Origenism really were just masking personal issues - and this became clear as the case developed and Theophilus stopped talking about Origen altogether and found other reasons to have John deposed.
So I would be inclined to tend to take these things at face value unless there's good reason not to, on the understanding that there's often more to it than
just face value. But that may be partly because I think in terms of ideas and philosophies rather than people and politics. Plus, I'd say that one can't really make sweeping statements about this kind of thing in general. Each case should be taken individually.
The Donatist case is especially awkward because it certainly did have political elements (resentment of the emperor) as well as, I think, genuine theological concerns - the latter had already surfaced in other disputes, such as with the Novatianists, so I think it's fair to say they were important to people. But even worse, Donatism was also an organistional schism. Indeed that's what it mainly was, especially in the later stages. I think that often when a church has split like that the schism retains a sort of momentum even long after anyone can remember what it was about in the first place. The Meletian schism at Antioch in the fourth century was like that. Or in modern times you might think of the split between Anglicans and Methodists, who are indistinguishable from each other. I'm sure that after a generation or two there were plenty of Donatists who knew or cared almost nothing about what had happened during the Decian persecution - which was when the whole thing began - and were Donatists simply because that's what they were.