Is the evolution and performance of cognition an asymmetric, directed process? The standard externalist definition of evolution as a mechanism of variation and selection cannot account for directed developments such as an increase in complexity of cognition. A separate cause which is responsible for complexification requires us to deviate from the usual description of cognition as ahistorical logical problemsolving: the anticipation-driven nature of behavior, and hence cognition based on a ratchet effect. On a structural level it is evident that the growth of behavioral competence, similar to biological structures, must build on previously available components, thus yielding a canalization of development. This unavoidably introduces asymmetry in the cognitive evolution. Numerous examples show the relevance of the proposed mechanisms in biology, psychology, and the artificial sciences. Cybernetics and Systems 32: 411–427. Running title: The Cognitive Ratchet Riegler, A. (2001) The Cognitive Ratchet—The Ratchet Effect as a Fundamental Principle in Evolution and Cognition. Cybernetics and Systems 32: 411–427.