An act of superstition touches the father of reason, humanist philosopher David Hume on Edinburgh's Royal mile. The ideas born during the Scottish Enlightenment shaped the modern world, revolutionising thought on commerce, politics and religion and spread abroad through empire. Voltaire claimed "We look to Scotland for all our ideas of civilisation". Of these ideas Hume was most influential. Despite his critique of superstition his foot has become a luck charm for students seeking good luck in exams. The liberal democracy he shaped was founded on the fruit of the earlier protestant reformation, a movement across western Europe spread from the pulpit of St Giles cathedral seen in the background and led by John Knox.