The role and value of diagrams in advancing human knowledge throughout history is evident in the literature. However, persistent evidence from the research and practitioner communities from across a range of disciplines points to difficulties and problems with understanding and using diagrams. Whether it is at the application level or as an abstract definition, our existing frameworks for understanding diagrams reduce the full meaning of diagrams to a single perspective or emphasis. This paper advocates placing multi-aspectual human functioning in a central role in the development of an enriched meta-approach to understanding diagrams. Two such aspects, namely, the spatial and symbolic, are essential to the understanding of diagrams across applications. The philosophical underpinnings and practical contributions of this approach to dealing with long standing problems of diagrams are discussed.