Author's personal copy Cultural-historical activity theory and the zone of proximal development in the study of idioculture design and implementation Action editor: Christian Onof Robert Lecusay * , Lars Rossen, Michael Cole University of California, San Diego, Laboratory of Comparative Human Cognition, Department of Communication, 9500 Gilman Drive, La Jolla, CA 92093-0503, USA Received 1 April 2007; accepted 29 June 2007 Available online 29 August 2007 Abstract For a large part of its history cognitive science has been grounded in views of the mind based on the traditional Cartesian dualisms. These dichotomies have been reinforced in particular by the view of the mind as an encased symbol-processing system ‘‘protected from the external world’’ (Newell, A., Rosenbloom, P. S., & Laird J. E. (1990). Symbolic architectures for cognition. In M.I. Posner (Ed.), Foundations of cognitive science, Cambridge, MA: Bradford Books/MIT Press, pp. 93–131:107). Cultural-Historical Activity Theory (CHAT) seeks to supersede Cartesianism, thinking about cognition and culture as mutually constitutive of each other. This approach analyzes thought processes as embedded in and manifested through systems of historically developing, culturally mediated activity. Con- sequently for CHAT, a basic unit for the study of human thought is joint mediated activity. In this paper we will discuss an example of research that follows the CHAT approach to the analysis of learning and development. The data sample is taken from a session of the Fifth Dimension, an after-school activity designed to implement CHAT principles in order to promote the cognitive and social development of adult and child participants alike. Ó 2007 Elsevier B.V. All rights reserved. Keywords: Cultural-historical activity theory; Zone of proximal development; Cognitive development; Learning, microgenesis 1. Introduction The absence of context and culture from the early his- tory of the cognitive sciences was, according to Gardner (1987), the result of a general attempt by cognitive scien- tists to ‘‘factor out these elements to the maximum extent possible,’’ (p. 41). The traditional vision of cognition framed human thinking as the manipulation of inner mental representations of an external world (the central processing unit metaphor). Computational models were viewed as a key way to study cognitive phenomena thus interpreted. These models assume cognitive processes that are invariant across contexts, cultures, and history. This theoretical vision set the agenda of cognitive science as a project of explaining the mind from the inside out. From this perspective the external/internal distinction is clear: processing goes on inside the head. Over the past several decades approaches challenging these foundational assumptions have emerged or been rediscovered within the cognitive and social sciences (Cole, 1996; Engestro ¨ m, 1987; Hutchins, 1995). These alternatives approach the problem of cognition from the outside in, bringing us to reevaluate the importance of culture in our theories of cognition (Hutchins, 2001). In this paper we focus on one such approach: Cultural-historical activity theory (CHAT). Rather than conceptualizing culture and cognition as two separate phenomena that interact in a 1389-0417/$ - see front matter Ó 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.cogsys.2007.06.012 * Corresponding author. Tel.: +1 858 534 4006; fax: +1 858 534 7746. E-mail address: rlecusay@uscd.edu (R. Lecusay). www.elsevier.com/locate/cogsys Available online at www.sciencedirect.com Cognitive Systems Research 9 (2008) 92–103