||An observation tool as an aid for building proofs
School geometry is endowed with an empirical and a deductive aspect. Though in history their role and importance varied, it is probably out of question that both aspects are essential for learning and knowing in geometry. Dynamic geometry systems by their nature favour the empirical aspect of geometry and promote conceptual understanding. We propose a different type of software that is aimed at promoting the deductive aspect of geometry. In simple terms, this software analyses geometric configurations (constructed in a dynamic geometry environment) and brings to light its geometric properties. The student can focus on selecting the relevant properties, organise the selected properties into a proof and supply the deductive arguments. We present the basic functionalities that we found useful or necessary for such type of software. Further research will show whether such approach improves the students’ ability to make deductive argumentations.