Jean Jacques Rousseau (17121778). Social Contract & Discourses. 1913.
The Social Contract or Principles of Political Right. Book III.
Chapter VII. Mixed Governments
STRICTLY speaking, there is no such thing as a simple government. An isolated ruler must have subordinate magistrates; a popular government must have a head. There is therefore, in the distribution of the executive power, always a gradation from the greater to the lesser number, with the difference that sometimes the greater number is dependent on the smaller, and sometimes the smaller on the greater.
Sometimes the distribution is equal, when either the constituent parts are in mutual dependence, as in the government of England, or the authority of each section is independent, but imperfect, as in Poland. This last form is bad; for it secures no unity in the government, and the State is left without a bond of union.
Simple government is better in itself, just because it is simple. But when the executive power is not sufficiently dependent upon the legislative power, i. e. when the prince is more closely related to the Sovereign than the people to the prince, this lack of proportion must be cured by the division of the government; for all the parts have then no less authority over the subjects, while their division makes them all together less strong against the Sovereign.
The same disadvantage is also prevented by the appointment of intermediate magistrates, who leave the government entire, and have the effect only of balancing the two powers and maintaining their respective rights. Government is then not mixed, but moderated.
The opposite disadvantages may be similarly cured, and, when the government is too lax, tribunals may be set up to concentrate it. This is done in all democracies. In the first case, the government is divided to make it weak; in the second, to make it strong: for the maxima of both strength and weakness are found in simple governments, while the mixed forms result in a mean strength.