In addition to ensuring liberty and justice, one of the most crucial things Montequieu talked about was the protection against an excessive centralization of power.
The separation of powers prevented an abusive tyranny or aristocracy from emerging and developing. Basing his model on the Roman Republic's Constitution, as well as the British government system, Montequieu noted how essential this was in their history by noting how none had been able to usurp power in those places.
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