The 18th Century: The Enlightenment
If the 16th century was that of the Renaissance and Humanism and the 17th century one of science, then the 18th century was called the century of reason, of lights, of knowledge (the Enlightenment period), the century in which previous efforts gave bore their fruit.
During this century it was finally believed that Reason was sufficient to explain the world without resorting to the supernatural forces and that man and nature were guided by laws which they had to discover. This assumption was based on the kindness of man and his ability to perfect himself through education (they were openly optimistic). These ideas were against, irrational and superstitious thinking (all that was not dictated by reason).
Those who professed this way of thinking were not great scientists or philosophers (like Descartes or Kant were) but they formed an elite of educated men, thinkers, philosophers, originally French with an optimistic vision. They believed that it was possible to change the world through education and by modifying customs; many were openly dedicated to this. They were advisors to the kings, they published and wrote encyclopedias and attempted to promote reforms in their countries, etc.
In regard to political ideas, although they were not directly revolutionary, these thinkers created the vocabulary and ideas that would be used in the French Revolution. We can mention to Montesquieu who developed the theory of the ‘division of powers’ as a way of guaranteeing a fairer form of government. Rousseau defended the idea of the ´Social Contract’, this was the idea that the governors and kings should rule and govern according to a contract based on the consent of the town or their subjects. There lies the idea of ‘popular sovereignty’, which is essentially a sovereign community which delegates power to its governors to represent them. A later philosopher was Voltaire, who was a great defender of ‘civil rights’ (judgment, religion, etc.)
During the century of the Enlightenment many of the kings accepted the recommendations of the enlightened rulers, who in some cases were ministers and advisors to the kings and adopted measures to modernize the country and introduce improvements in areas such as health, education, industry, etc. However, although they accepted enlightened ideas and reforms in many aspects; the power of the kings continued to be total and absolute. This is why the expression, `All for the people, but without the people´, became a slogan, representative of this enlightened despotism. This was in reality a contradiction with the political ideals of the Enlightenment and as a result the enlightened absolutism had no future. In fact, in France, the Revolution began with an ´enlightened reform´. In addition to the case of the Bourbons in Spain and especially Carlos III, the examples of Catherine the Great in Russia and Federico II of Prussia can also be quoted. All of them modernized the institutions and other aspects of their countries.