Answer to Question 1
According to Marx, historical change is the result of a dialectical process that creates a new social order. In a society, there is an arrangement of power (a thesis). However, there are built-in oppositions to this arrangement of power. Marx referred to these oppositions as the antithesis. Eventually, there is a struggle between the thesis (those currently in power) and the antithesis (those opposing this arrangement in power). The result is a synthesis, a new arrangement of power. This new social order, then, becomes the thesis that will be challenged by its own antithesis. This process will continue until a classless society (the synthesis) is created.
Answer to Question 2
Unilinear theories assume that all societies evolve from the simple to the more complex through the same sequence of stages. Multilinear theories also assume that all societies evolve from smaller to larger, more complex forms as they adapt to their environments. However, they differ from unilinear theories in that they suggest that societies can take different routes in their development to larger, more complex societies. These theories have largely been rejected because the core assumption is that progress is always beneficial to a society. The problems of Western culture and the beneficial aspects of traditional cultures have illustrated that this idea of progress is not always true.
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