Et tu, brute?

Metaphysics is a norm-governed enterprise. It has rules; rules that are, ultimately, to be subsumed under the general normative principles that govern philosophy at large. But it has never been clear, at least to me, what the rules of the philosophical game are or, indeed, should be. There may not even be a single, univocal set of such rules by which everyone operates; there may not be a single philosophical game that everyone is playing. What we do have, however, are intuitions, elicited on a case-by-case basis, about when a move made within an area of philosophy such as metaphysics seems illegitimate. Sometimes something jars. One move, in particular, stands out for me. When someone invokes a primitive to get their theory out of strife, or when some feature of a theory is taken as primitive in order to avoid giving an analysis of that feature (because no such analysis has thus far succeeded) I am suspicious. Of course, there are clearly circumstances in which the invocation of primitives is a legitimate move to make. Everyone gets to use some primitives in the context of theory building, and everyone is, within reason, entitled to spread their primitivity where they like. If one wishes to cast their primitiveness upon this or that feature of their theory, then I want to say that, for the most part, they can.