The idea that the Primordials cannot think outside defined parameters is an exaggeration. They cannot act with their Excellency outside of their paradigm, which—in practice—tends to dramatically limit their methods of comprehension.
The key words there, in case you missed it, were "in practice." On behalf of the writers of the latter half of Infernals—myself, Eric Minton, Michael Goodwin—I apologize for giving the fanbase the impression that Primordials could never ever ever with sugar on top think or act outside the bounds of their Excellency. They totally can. They just don't get any dice for the roll, nor do they usually have a dice pool. Usually this means an automatic failure for whatever they're attempting…which, again, leads us back into the "when all you have is a hammer" mentality.
Virtue channelling can change that, as Yeti noted, though stunting does not (they do, however, get motes back for the action they attempted to perform, should it succeed). It's just that when you embody a paradigm, and you get ALL YOUR DICE for a certain type of action, you tend to only perform those actions.
It becomes an act of heroic will—coupled with a mental paradigmatic shift, and subsequent shift back—to do otherwise. Autochthon in particular was very limited by this myopia, and lombotomized himself to feel (and act on) empathy.