The Enlightenment is the fountainhead of modern secular Western values: religious tolerance, freedom of thought, speech, and the press, of rationality and evidence based argument. Yet why, over three hundred years later is the Enlightenment so profoundly misunderstood as the expression of soulless calculation? Ritchie Robertson goes back from approximately 1680 to 1790 to reveal what this much-debated period was really about.