According to marx, human history shows that struggle develops between the thesis and its antithesis, leading to a synthesis. marx called this historical change a(n)

The answer id dialectal process. According to Hegel, "dialectic" is the technique by which human past clarifies; that is to say, the past develops as a dialectical procedure. Karl Marx stated that human history reveals that struggle grows in the middle of the thesis and its direct opposite, bringing it into a synthesis. 

the answer to your question is,

old stone age.

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