Nonaka and takeuchi’s highly influential account of tacit–explicit knowledge-conversion in japan’s knowledge-creating companies has been instrumental in knowledge management’s institutionalisation of michael polanyi’s distinction between ‘tacit knowledge’ and ‘explicit knowledge’. But tacit knowledge has been misunderstood and what nonaka and takeuchi claim in the name of explicit knowledge does not make sense. Whereas polanyi was concerned with the discovery of absolute truth about ontological reality, nonaka and his colleagues insist that truth is ‘in the eye of the beholder’. Yet, nonaka et al.’s implicit nihilism seems to have gone unnoticed. Many people talk about explicit knowledge as if it existed on a par with scientific knowledge: a tangible commodity that is ‘as real as rocks’. Arguably, nonaka and takeuchi have offered a ‘lesson from japan’ that has distorted polanyi’s concept of tacit knowing, inspired unwarranted faith in the viability of ‘explicit knowledge’, and ignored the significance of power mediated by ‘high-context’ communication. This paper uses ernst von glasersfeld’s work on radical constructivism to make sense of polanyi’s insights into tacit knowing without invoking notions of metaphysical truth. With reference to knowing, learning and communicating in japanese organisations, we suggest that a radical constructivist approach offers a viable alternative to nonaka and takeuchi’s knowledge-conversion model.