Enlightenment is a loose term to capture the thought of certain intellectuals who, influenced by the success that science had in explaining the natural world, believed something similar was possible to explain the social world. This led them to argue that political and social arrangements should be critiqued to the extent that these were based on superstition rather than reason. (Key intellectual figures included Adam Smith, David Hume in Scotland, Immanuel Kant in Prussia and French figures such as Voltaire and Montesquieu.)

A key source in defining the Enlightenment is Kant (1784). Kant stresses his belief in our capacity to think for ourselves (‘immaturity is the inability to use one’s own understanding without the guidance of another’). Here enlightenment thinkers usually had in mind religion, prejudice and tradition as the suffocating guidance of another. By exercising reason we become better, fuller human beings, while at a social level we will have more rational institutions, a rule of law and a democratic public sphere.

Enlightenment thinkers held differing positions on knowledge creation but tended to have faith in the power of reason and application of scientific thinking. In terms of method this led to a concern for experiment and observation, tolerance of other views and a more fallible idea of knowledge.

Ideas of the enlightenment inform how we think and what we expect of political and social institutions today. However, the Enlightenment legacy has been subject over time to critique from different directions, including:

• conservatives who drew on the example of French revolution, and the terror that ensued, to say this is what happens when society is not held together by tradition and indeed official religion. The charge is also made that the exercise of reason can be elitist, i,.e. 'our job is to enlighten you’.
• romantics who saw this celebration of reason as neglecting more aesthetic and intuitive ways of understanding the world
• in our own time by post modernist and post structuralist thinkers who doubt whether there is an impersonal reason as posited by Kant.

For more:

Kant (1784) An answer to the question: 'what is enlightenment' in H. Reiss (ed) Kant Political Writings, Cambridge: CUP - this is accessible online via the library or indeed from many other online sources.