Human development theories differ in “context sensitivity,” covering those stressing development stages and those stressing continuously progressing changes. The former theories differ in whether, how and why the stages are regarded as being generalized across domains, i.e. their generality claims. Piaget’s developmental stage theory of logical complexity of children and adolescents fulfill “strong” such claims, including fixed stage sequentiality of increasing complexity levels and higher stage structures integrating earlier ones. His theory has inspired a number of adult development stage theories with varying generality claims. These provide suggestions of stages and stage transitions reaching beyond “pure” cognition, integrating more of e.g. emotional, value and moral dimensions. From a neo-Piagetian perspective, core generality aspects seem to concern on the one hand logical reasoning and on the other hand meaning-making. This raises questions of how these aspects are related to each other in terms of stage structures and transformations.The aim of the article is to discern general features in adult development stage structures and transitions, in terms of logical reasoning and meaning making. This is carried out by a “thought experiment” interrelating two theories that differ in these respects but that are both based on Piaget’s theory, namely Robert Kegan’s constructive developmental Subject-Object Theory (SOT) and Michael Common´s behaviouristic Model of Hierarchical Complexity (MHC). This comparing approach concerns the 3rd, 4th and 5th order of consciousness as well as transitions between these according to SOT, and order 9 to 12 and corresponding transitions according to MHC. The thought experiment indicates that the generality claims of both models can be argued for without one of them necessarily being subordinated to the other one. Both theories are interpreted as differing but partly overlapping structures of coherence, while also being involved in transformative thesis-antithesis-synthesis processes. The possible interrelatedness between logical reasoning and meaning making is considered and discussed, as well as the relevance of differing generality claims, and contrasting subjectivistic and objectivistic “scientific positions.” Finally, it is argued for the need of contextualizing adult development theory and research by relating it to postindustrial societal demands and challenges in terms of e.g. a “transform-actional” approach.”