Evolution and Cognition Vol. 9 (no. 1):49-56. 2003 Short description A distinction between an epistemological and an ontological concept of consciousness is proposed Abstract Several studies have addressed the differences between implicit and explicit learning. Focus has been on tacit, automated, non-conscious, procedural and incidental learning as opposed to symbolically represented learning, expressed in words. Separation of implicit and explicit learning is generally based on the absence or presence of conscious awareness of the learned material. In this paper, the representational modes of different learning strategies are explored from a phylogenetic perspective, with emphasis on detachment from context. The notion of vertical and horizontal learning is introduced to clarify their applicability to different contexts.