Liberty is not suited to every climate, and thus is not universally attainable. Rousseau's analysis of freedom and climate focuses on how the people provide for government spending. In all states, the government consumes a great deal, but produces nothing. It receives what it consumes from the surplus that its citizens create. Thus, the state can only survive as long as the people produce more than they need. Some governments are more voracious than others, and thus place greater burdens on their people.
Rousseau argues that the economic burden has less to do with the size of the government and more to do with the circulation of goods. In a democracy, the executive and legislative branches are the same, and taxes are returned to the people in the form of government spending. In a monarchy, taxes support the private interests of the king, and circulation is slow or nonexistent. In other words, the people are least burdened under a democracy and most burdened under a monarchy. It follows that monarchies are suited to wealthy nations, which produce large surpluses, and that democracies are suited to poor nations.
Climate determines what form of government the state will employ by influencing the amount of surplus. Because hot countries usually have the most fertile soil and produce the most surplus, they should have a monarchy whose luxury will consume the excess goods. In contrast, cold countries produce a moderate surplus and should have a democratic form of government.
It is impossible to determine which form of government is ideal without knowing the particular conditions of each nation. However, Rousseau does provide one measure of governmental efficacy. An increasing population demonstrates that the government is promoting the prosperity of its members. Rousseau asserts that the government under which "the citizens become populous and multiply the most, is infallibly the best government."
Although Rousseau praises civil liberty throughout The Social Contract, he asserts that not all people can attain it. Whether a people can form a free society is dependent on their natural resources. Climate influences how much a country will produce and thus determines whether it suited to barbarism, despotism, or good polity. The effect that climate has to encourage or prevent liberty creates an interesting tension within Rousseau's work. By exchanging their natural freedom for civil freedom, people gain a sense of morality, according to Rousseau. Because he argues that climate may inhibit liberty, he implies that certain people will be incapable of behaving morally due to their geographic region.
Rousseau bases his analysis of climate and government on how taxes circulate within a society. In a democracy, taxes are soon given back to the people in the form of government spending. Thus, democracy burdens citizens the least despite having a large number of magistrates. Conversely, a monarchy is the most difficult for the people to endure because circulation is slow and very little is returned to the people through government spending.
Thus, Rousseau argues that a country's government must agree with its productive capabilities. Perhaps showing the weakness of his theory, he does not allow for it to be disproved. He asserts that even if hot areas were filled with democracies and cold one with monarchies, this fact would not refute theory. It would only show that other factors overshadowed climate in determining a country's government.
Although Rousseau declares that an increasing population is the best measure of analyzing a government's performance, he does not give a clear reason of why this is so. There are numerous examples of nations that were poorly governed yet increased their populations. Perhaps Rousseau's decision to use population as an indication of good government stems from his desire to promote agriculture.
An increase in population can only occur if there is a corresponding increase in agricultural productivity. A state that encourages agriculture cultivates all usable land and has a population that is spread throughout its entire territory. In contrast, a state that neglects agriculture has a declining population that is concentrated in the cities. Importantly, Rousseau disapproves of urban life, believing that it promotes idleness and luxury.