Absolute Truth means an ideal which is completely in correspondence with Nature, a synonym for God. Abstract and Concrete Abstract and Concrete are philosophical concepts concerned with the development of conceptual knowledge. For Hegel and for Marx, the contrast between abstract and concrete does NOT mean the contrast between ideals. Rather 'A concrete concept is the combination of many abstractions'. A concept, such as a number or a definition, is very abstract because it indicates just one of millions of the aspects that a concrete thing has, ignoring all other aspects.
Concepts are the more concrete the longer and more thorough they are described.