 The heart of the eighteenth century Enlightenment is the loosely organized activity of prominent French thinkers of the mid-decades of the eighteenth century, the so-called “philosophes”(e.g., Voltaire, D’Alembert, Diderot, Montesquieu). The philosophes constituted an informal society of men of letters who collaborated on a loosely defined project of Enlightenment exemplified by the project of the Encyclopedia (see below 1.5). However, there are noteworthy centers of Enlightenment outside of France as well. There is a renowned Scottish Enlightenment (key figures are Frances Hutcheson, Adam Smith, David Hume, Thomas Reid), a German Enlightenment (die Aufklärung, key figures of which include Christian Wolff, Moses Mendelssohn, G.E. Lessing and Immanuel Kant), and there are also other hubs of Enlightenment and Enlightenment thinkers scattered throughout Europe and America in the eighteenth century.