Recent scholarship on the Scottish Enlightenment has emphasized the increasing importance, in the last decades of the eighteenth century, of the concept of race. Yet race was a conceptual, moral, and taxonomic puzzle for Scots intellectuals such as Adam Ferguson (1723-1816). While the influence of Ferguson's published works has received wide scholarly attention, the content of his teaching has not. His surviving moral philosophy lecture notes offer us a window into the development of thought on race at the disciplinary intersections of moral philosophy and natural history, and the crossroads of Edinburgh's curricula and Britain's Empire.