This paper gives experimental evidence against the claim that speakers’ intuitions support semantic relativism about assertions of epistemic modal sentences and uses this evidence as part of a broader argument against assessment relativism. It follows other papers that reach similar conclusions, such as that of Knobe and Yalcin (Semant Pragmat 7:1–21, 2014). Its results were achieved simultaneously and independently of the more recent work of Kneer (Perspectives on taste. Aesthetics, language, metaphysics, and experimental philosophy. Routledge, 2022). The experimental data in (...) this paper supports two claims. The first is that, as Knobe and Yalcin (Semant Pragmat 7:1–21, 2014) also found, speakers diverge in their judgments about the truth-values and about the appropriate retraction of epistemic modal claims. The second is that speakers diverge in their judgments about when a retraction is appropriate and when it is required. This divergence was not tested by Knobe and Yalcin (Semant Pragmat 7:1–21, 2014) but aligns with the results independently reached by Kneer ((Kneer, Synthese 199(3–4): 6455–6471; Perspectives on taste. Aesthetics, language, metaphysics, and experimental philosophy. Routledge, 2022), and supports the arguments previously developed by Marques (Synthese 199(3–4): 6455–6471). The present studies tested the intuitions of both North American English speakers and of peninsular Spanish speakers, whose judgements on the topic had never been tested. The broader argument involves the relation between required retractions and falsity. (shrink)