The nineteenth century

what can and cannot be (re)presented—on models and Kindergartens

pp. 113-269

in: Michael Friedman, A history of folding in mathematics, Basel, Birkhäuser, 2018

Abstract

Apart from the growing acceptance of the fold as a legitimate proof practice in geometry, two main mathematical traditions in the nineteenth century used, integrated and conceptualized folding, each showing its advantages and limitations.