Chapter 3: Onlookers and Actors in the Drama of Existence:Complementarity in Cultural Psychology and Its Existential Aspects

In this text, I wish to offer some thoughts on the concept of complementarity and its relevance for psychology. Jaan Valsiner’s (2013) reflections on Niels Bohr’s notion of complementarity—in relation to cultural psychology specifically—is a highly relevant starting point for anyone who wants to understand the links between conceptual thought in the disciplines of physics and psychology. As Valsiner makes clear, Bohr’s innovative solution to the existence of opposite perspectives on the physical world (e.g., particle-wave aspects of physical objects) was to assert that both perspectives are equally true, although not applicable at the same moment. The physicist can approach the basic physical phenomenon, using her experimental apparatus, either as a wave or as a particle, but measuring the properties of one aspect precludes knowledge of the other. There is no dualism at work here, but, according to Valsiner (and Bohr), a wave-particle duality.