at the same time, understanding that proof is required to demonstrate that
geometrical statements are true. Further data show that attending more closely to the
matter of the ‘Generality of proof’ can disturb students’ beliefs about experimental
verification and make deductive proof meaningful for them. It could be interesting to
interpret these results with the same tools as Panoura and Gagatsis: didactical
contract and geometrical paradigms. It seems that the conclusions are very close but
in different context.