Abstract
It is argued that we should distinguish between an ‘early Hume’ and a ‘mature Hume’ on causality. In his early period, represented by the Treatise, Hume had not yet adopted Newtonian active principles. In the mature period, however, represented in particular by the First Enquiry, his theory of causation has been transformed by a reception of Newton. This leads Hume to drop the condition of contiguity, which had excluded action-at-a-distance in the Treatise. It also leads him to allow real necessary connexions in nature which are inaccessible to us just as the real cause of gravitation was thought by Newtonians to be unknown