We refute criticisms by Del Santo and Horvat towards our paper "Quantum principle of relativity": most of their counterarguments can be dismissed, and the rest provides further evidence to our claims.
In this short note we reply to a Comment by Callegaro et al. [Callegaro, Pennecchi, and Bich, Phys. Rev. A 102, 036201 (2020)] that points out some weakness of the model of indeterministic physics that we proposed in our work [Del Santo and Gisin, Phys. Rev. A 100, 062107 (2019)], based on what we named ``finite information quantities'' (FIQs). While we acknowledge the merit of their criticism, we maintain that it applies only to a concrete example that we discussed in our work, whereas the main concept of FIQ remains valid and suitable for describing indeterministic physical models. We hint at a more sophisticated way to define FIQs which, taking inspiration from intuitionistic mathematics, would allow the criticisms in the preceding Comment to be overcome.