The importance of Adam Ferguson as part of the Scottish Enlightenment has been well established, with concentration on his social and political thought. George Turnbull has not been as well studied, but the valuable recent anthology by M. A. Stewart and Paul Wood has incited new interest. This paper selects a narrow aspect of their thought, their views on the social role of knowledge, which show common as well as complementary aspects. As educators who published their enhanced class notes, their (...) concern for providing positive motivations for their students is evident from their writings. Moral philosophy courses in general attempted to prepare graduates to assume responsible roles in society. Turnbull emphasizes the inspirational value of order and beauty in nature, while Ferguson's particular interest is in the value of learning efforts and knowledge development as part of the cumulative progress of civilization. We believe that a joint review of their thought can provide a rich source of possibly inspirational and motivational themes that could be helpful for professionals and educators in any culture. These topics are discussed here in the broader context of the Scottish Enlightenment. (shrink)