The purpose of Montesquieu's theory of separation of powers is to

Montesquieu's theory of separation of powers aims to prevent tyranny by dividing the powers of government into three separate branches: the legislative, the executive, and the judiciary. Each branch has its own distinct powers and functions, and they are intended to provide a system of checks and balances on one another. This means that no one branch has complete control or authority over the government, and that any abuse of power by one branch can be checked and balanced by the other branches. The ultimate goal is to safeguard individual liberty and promote the rule of law.