For all the challenges we face in the modern world, those of us in first world democracies live lives which have seemed miraculous to our forebears of a few centuries ago. With modern medical science, we can easily treat injuries and illnesses which used to be fatal. We have plentiful food, rights to freedom of speech and religion, access to public education, and can vote for our leaders. We still have a long way to go to free ourselves of injustice, poverty and want, but no human societies have ever gone further. Why the Enlightenment Matters goes back to the seventeenth century to explore how we broke out of old ways of thinking to move towards the scientific method, industrial revolution, liberal democracy, and human rights. Looking back, it's easy to see these developments as inevitable. In reality, huge barriers stood in the path of progress. Today, with the world grappling with the rise of new forms of authoritarianism and the re-emergence of old ones, it is more important than ever to understand what makes our societies successful. And, from that, how we can confidently face the threats of the future.