Powerful ideas because they are taken as true ordering principles of society. Ordering of universe becomes cosmological we are civilized, others are monsters. Ideas of ethnicity, class, nationhood self-justify. Culture concept came from German project to counter 18th century rationalism. Said universality was wrong, peoples are different.
Anthropology comes from notion of elaboration of differences.
Boas critique is that culture is of bits and pieces, tinker-toy common elements create diverse wholes. Can t say one is better than another. Human ideas and institutions are constantly changing, being rearranged, borrowing, inventing, diffusing. Culture as a concept is not explanatory. Ideas to create coherence political programs people buy into.