Aporia
A philosophical term, describing an insoluble contradiction or paradox in a text’s meanings. Apparently plays a central element in Derrida’s philosophy (more study needed here). Also “perplexity”. Intellectural paralysis. Conceptual puzzlement. Etymology goes back to “lacking a way/path”. By extension, an expression of doubt or befuddlement. A crisis of choice, of action and identity, as well as of belief. Adjectival form is aporetic: “an aporetic encounter”. Epistemic emptiness.
Not purely negative—can also function as a stimulus to some kind of breakthrough.