This first chapter introduces the proposal of an evolutionary account of law, understanding rules and institutions as the unintended outcome of individual interactions over time. It highlights the eighteenth-century Scottish Enlightenment—with thinkers like Adam Smith, David Hume and Adam Ferguson—as pioneers of evolutionary social views, predating Darwin. Antecedents include Bernard de Mandeville’s notion of ‘unintended consequences’ and Francis Hutcheson and Lord Shaftesbury’s ideas of an innate ‘moral sense’ and ‘benevolence’. David Hume conceived justice as an ‘artificial virtue’ arising from a ‘mutual sense of common interest’ to address the scarcity and instability of material possessions, considering property security a sine qua non for society. Adam Smith’s moral philosophy, centred on sympathy and the standpoint of the ‘impartial spectator’, provides an evolutionary explanation of justice and of the judiciary. The chapter concludes by emphasising Adam Ferguson’s influential concept: institutions are “the result of human action, but not the execution of any human design”, a cornerstone for contemporary evolutionary social theories.