Abduction in Generating Conjectures in dynamic Geometry through Maintaining Dragging

This paper introduces two types of abduction associated to two different ways of generating conjectures that arise from using a particular dragging modality in dynamic geometry. We refer to such dragging modality as maintaining dragging (MD). A first use of MD relies on physical dragging-support and it seems to lead the solver “automatically” to the formulation of a conjecture. In this case the abductive reasoning seems to occur at a meta-level and to be concealed within the MD instrument. On the other hand, some of our data shed light onto a different way of generating conjectures which is rooted in use of MD but is “freed” from the physical dragging-support. In this case abductive reasoning seems to occur at the level of the dynamic exploration.