The Enlightenment led to rational ideas about government. Kings no longer ruled by divine right; rather, government was to be rational. For some people, this meant a rise in republican thought—because it was thought that the people could best govern themselves according to what they needed. Critics of republicanism thought that the people were too fickle and selfish in their wants and that they looked to enlightened monarchs or small ruling groups.

The Enlightenment also led to the concept of natural law. These are laws that exist in the absence of government and are considered universal. From natural law one gets natural rights that cannot be given by government; rather, these are inherent in human nature. According to Locke, these natural rights are life, liberty, and property.

Governments using Enlightenment ideals have interpreted these differently. Jefferson, author of the Declaration of Independence, modified the last point from "property" to "the pursuit of happiness." The Enlightenment led to multiple treatises on governance as people used rational arguments as to the nature of government and how government should be administered.

The Enlightenment also led to colonialism. The idea behind a nation establishing an empire was to enrich itself. The idea behind mercantilism was to increase exports and minimize imports in order to increase a nation's wealth. This meant that nations were constantly on the lookout for more raw materials. Colonists could only trade with the mother country in order to enrich it.

The Enlightenment led to new ideas of governance that were based on people's basic nature and reason. Though it failed to take into account that people do not always act in their own long-term interests, the Enlightenment did contribute heavily to the study of political science and new ideas of macroeconomics.

As with so much else in the Enlightenment, the key test was reason. The legitimacy of government was derived not from God or tradition, but from whether it was rational and reflected humankind's inherently rational nature. The thinkers of the Enlightenment looked upon government in formal, instrumental terms. It was not necessarily a good in itself; it was only good insofar as it served rational ends.

The problem with this way of thinking is that it sacrifices substance for form, what is right for what is efficient, and the means for the end. There is no real thought given to what government should actually do, but how it should do it. In practice, this formally rational, instrumentalist approach to government has led to some disastrous consequences. Most people are familiar with totalitarian regimes cynically using the slogan "The end justifies the means" to defend repressive policies.

This is an example of what can happen when we look upon government as simply a rather useful tool for pursuing rational ends. The Soviet Union, for instance, pursued a perfectly rational policy of wanting to catch up with the Western powers in terms of industrial output. However, the means they used to achieve this goal involved suffering on a massive scale.

The various colonial empires and their governments were also devoted to ostensibly rational ends. Empires greatly increased the wealth of the mother country; they increased trade and manufacture; they spread the benefits of civilization far and wide to the darkest, remotest corners of the world. Sadly, we need hardly remind ourselves of the immense plunder and exploitation which this involved.

Of course the thinkers of the Enlightenment cannot have been expected to predict all the baleful consequences of their conception of government. However, hints of what might happen were there right from the start. Enlightenment thinkers such as Voltaire were passionate advocates of so-called "Enlightened despotism," whereby tyranny was perfectly justified so long as it was geared to serve rational ends. Underlying this concept was an elitist disdain for the common people, seeing them as little more than ignorant, priest-laden, superstitious dupes who needed the strong hand of an enlightened despot to guide them toward the sunlit uplands of a thoroughly rational polity.

The Enlightenment affected people’s attitudes about government in two main ways.  It changed what they thought about who should govern them and it changed what they thought about the purpose of government.

Before the Enlightenment, essentially everyone agreed that countries should be governed by monarchs.  They believed that God had appointed certain people to rule over others.  This seemed to them like the logical way to run a country. With the Enlightenment, however, people came to think that this did not make sense.  They started to think that the people should be able to choose their own rulers.  This led them towards believing in democracy.

When monarchs ruled countries, it was pretty well understood that they ruled for their own benefit first.  They were the embodiment of their country and so it was right for them to do things that would benefit themselves.  This changed during the Enlightenment.  People started to think that the people were more important.  They started to think that government was supposed to help the people, not the rulers.  They came to believe that the government was supposed to protect the rights of the people.

In these ways, the Enlightenment changed many people’s beliefs about who should govern and what the purpose of the government should be.