<p>Disinformation is often defined as misleading content intended to instill false beliefs. But this definition is too narrow. We need to focus instead on its broader epistemic effects. Indeed, some disinformation campaigns rely not on sharing falsehoods but on spreading what I call grievance narratives. These narratives exploit the (real or imagined) grievances of a community and frame them as signs of a deeper systemic problem, typically instigated by a powerful and hostile group. In this way, they legitimize and amplify aversive emotions and foster a negative orientation toward the world, one in which emotions like resentment or indignation feel continuously warranted. Now, grievance narratives are particularly harmful because they epistemically isolate their targeted audience. In short, they undermine the network of information sources that a community can rely on and, as such, they obstruct access to epistemic goods, such as knowledge and understanding. This stems from a key feature of these narratives: namely, they polarize the world between those who recognize the forces responsible for the community’s suffering and those who don’t. The latter are portrayed as not merely mistaken, but as either hostile or complicit with those to blame. In this way, grievance narratives systematically foreclose any alternative explanation of the community’s experiences, leaving them with little more than a single narrative to trust.</p>