Final answer:
The unilinear theory of cultural evolution, as put forth by Lewis Henry Morgan, posited a linear progression of cultural stages from savagery to civilization, driven by technological advances, which has since been criticized for its oversimplified view of cultural development.
Step-by-step explanation:
The unilinear theory of cultural evolution, developed by Lewis Henry Morgan in 1877, proposed that all cultures evolve through the same set of stages: from savagery, through barbarism, to an ultimate stage of civilization. Morgan's unilineal evolution focused on the technological advancements as the primary driver of cultural progress. He suggested that better ways of making things led to new societal patterns and thoughts. However, this theory faced criticism from anthropologists like Franz Boas, who argued that cultures evolve along their own unique historical trajectories, influenced by constant interaction with other cultures through trade, migration, and conquest. Instead of a linear progression, Boas highlighted the importance of cultural diffusion and a more complex understanding of cultural exchange and development.