 Within the descriptive project the vagueness challenge can be understood as arguing that our intuitive, commonsense notion or notions of cause are too vague to be given philosophical analyses precise enough to be able to play a legitimate role in the mathematized sciences. To the extent that physicists themselves engage in causal talk, this has to be understood as part of an informal framework within which physicists talk about theories but not as part of the formally rigorous and precise content of physical theories themselves (Earman 2011). One could imagine an analogous challenge as part of the functional project, even though here the criticism, if successful, would point to limits of the project of conceptually re-engineering causal notions and would show that causal concepts are so vague as to resist sufficient philosophical precissification.