Social and cultural norms are defined as shared rules or expectations that govern what is acceptable in a group, and reviews of the literature say these norms permeate human life and shape behavior. (ncbi.nlm.nih.gov) Cross-cultural moral-judgment research also finds that morality is embedded in the social systems and values of each culture, with different cultures treating some acts as transgressions in one setting and acceptable conventions in another. (frontiersin.org) So the claim is well supported as a general statement that culture helps determine what people regard as socially acceptable, though “dictates” is stronger than the usual academic wording of “shapes” or “influences.” (ncbi.nlm.nih.gov) Sources: National Academies Press/NCBI Bookshelf, “Addressing the Social and Cultural Norms That Underlie the Acceptance of Violence” (`https://www.ncbi.nlm.nih.gov/books/NBK493719/pdf/Bookshelf_NBK493719.pdf`); PubMed/Current Opinion in Psychology, “From one mind to many: the emerging science of cultural norms” (`https://pubmed.ncbi.nlm.nih.gov/29506794/`); Frontiers in Psychology, “Universality and Cultural Diversity in Moral Reasoning and Judgment” (`https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2021.764360/pdf`).