It was composed of many competing theories by various anthropologists and sociologists, who believed that Western culture is the contemporary pinnacle of social evolution.

At the same time, Christianity taught that people lived in a debased world fundamentally inferior to the Garden of Eden and Heaven.

The Enlightenment thinkers often speculated that societies progressed through stages of increasing development and looked for the logic, order and the set of scientific truths that determined the course of human history.

Georg Wilhelm Friedrich Hegel, for example, argued that social development was an inevitable and determined process, similar to an acorn which has no choice but to become an oak tree.

While earlier authors such as Michel de Montaigne discussed how societies change through time, it was truly the Scottish Enlightenment which proved key in the development of cultural evolution.

Although Imperial powers settled most differences of opinion with their colonial subjects with force, increased awareness of non-Western peoples raised new questions for European scholars about the nature of society and culture.

Emerging theories of social evolution reflected a belief that the changes in Europe wrought by the Industrial Revolution and capitalism were obvious improvements.

Industrialization, combined with the intense political change brought about by the French Revolution and US Constitution which were paving the way for the dominance of democracy, forced European thinkers to reconsider some of their assumptions about how society was organized.

The term "classical social evolutionism" is most closely associated with the 19th-century writings of Auguste Comte, Herbert Spencer (who coined the phrase "survival of the fittest") and William Graham Sumner.

This progress is forced through the development of human mind, and increasing application of thought, reasoning and logic to the understanding of world.

The industrial society has a goal of production and trade, is decentralised, interconnected with other societies via economic relations, achieves its goals through voluntary cooperation and individual self-restraint, treats the good of the individual as the highest value, regulates the social life via voluntary relations, and values initiative, independence, and innovation.

Morgan disagreed with the accusation of unilinealism, writing:In speaking thus positively of the several forms of the family in their relative order, there is a danger of being misunderstood.

He stressed that humans create goals for themselves and strive to realise them, whereas there is no such intelligence and awareness guiding the non-human world, which develops more or less at random.

The early 20th century inaugurated a period of systematic critical examination, and rejection of unilineal theories of cultural evolution.

Cultural anthropologists such as Franz Boas, typically regarded as the leader of anthropology's rejection of classical social evolutionism, used sophisticated ethnography and more rigorous empirical methods to argue that Spencer, Tylor, and Morgan's theories were speculative and systematically misrepresented ethnographic data.

They therefore argued that any attempt to use this theory to reconstruct the histories of non-literate (i.e. leaving no historical documents) peoples is entirely speculative and unscientific.

Boas in his culture history approach focused on anthropological fieldwork in an attempt to identify factual processes instead of what he criticized as speculative stages of growth.

Critical theorists argue that notions of social evolution are simply justifications for power by the elites of society.

Finally, the devastating World Wars that occurred between 1914 and 1945 crippled Europe's internal confidence shaking the remaining belief in Western civilization's superiority.

After millions of deaths, genocide, and the destruction of Europe's industrial infrastructure, the idea of linear progress with Western civilization furthest along seemed dubious at best.