Abstract: Contemporary research on animal consciousness is often caught in an epistemological predicament over whether the evidence is sufficient,a predicament rooted in a categorial displacement between two notions of “criteria”.Recent work,represented by Birch and colleagues,has developed a set of criteria for assessing animal sentience and uses them as empirical indicators for inferring inner states;the “criteria” Wittgenstein discusses in the Philosophical Investigations and his later manuscripts are,by contrast,grammatical conditions constitutive of the use of psychological predicates,revealing the normative dimension of animal consciousness.Failing to distinguish clearly between these two kinds of criteria,contemporary debate locks a question that properly belongs to grammar into a framework of evidence-accumulation and is thereby driven to an impasse.The controversy over octopus pain is a clear case in point.The later Wittgenstein's legacy on animal minds points to a reorientation of inquiry:from asking whether there is sufficient evidence that animals possess inner states to examining which animal behaviors,within our form of life,already constitute criteria for the use of psychological predicates.This reorientation not only helps contemporary research on animal consciousness move beyond the predicament just described but also offers illuminating conceptual resources for current debates on AI consciousness.