ABSTRACT
This chapter explains some hypotheses and considerations regarding the conditions in which it can occur. It discusses a rather unique case, that of a Sienese painter of the 1400s, Sano di Pietro, who repeatedly used an iconographic scheme, chosen probably for its expressive significance, which produces in the observer the swing effect. While in the field of decoration the use of contour rivalry and the swing effect is for purposes of embellishment, in some types of graphic and pictorial production it can be induced by the kind of technique used, at the same time contributing to giving expressiveness to the image. In the multi-faceted field of graphic and pictorial representation various examples of the swing effect can be found, examples which, corroborate the analysis so far carried out and confirm, the role of dynamics as a vehicle of expression and allow to draw some indications of the ways visual thinking functions.
