What was the historical reason for the separation of powers?

The separation of powers is a political principle in some forms of government, in which the legislative, executive and judicial powers of the State are exercised by different government bodies, independent of each other. This is the fundamental quality that characterizes democracy.

Montesquieu argued that "every man who has power is inclined to abuse it; He goes until he finds limits. In order that power can not be abused, it is necessary for the disposition of things to detain power". In this way, the vigilance of the three powers among themselves is entrusted, since each one of them supervises, controls and stops the excesses of the others to prevent, by own ambition, that one of them predominates over the others. It can be contrasted with the merger of powers and separation of functions in parliamentary systems, where the executive and the legislature are unified, because the legislature appoints the executive.  

This doctrine does not refer only to the separation and balance of the three classic powers of the Government, but to the need to divide the political power where it is located, be it in the municipal, regional or national sphere, in order to guarantee political freedom and avoid abuses of power, through the surveillance and reciprocal control of separate powers.

i confess that there are several parts of this constitution which i do not at present approve, but i am not sure i shall never approve them: for having lived long, i have experienced many instances of being obliged by better information or fuller consideration, to change opinions even on important subjects, which i once thought right, but found to be otherwise. it is therefore that the older i grow, the more apt i am to doubt my own judgment, and to pay more respect to the judgment of others.

mexico south america

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