The evil epsilon or it is not reasonable to be a heretic mathematician

Abstract

It was clear to Berkeley and Robinson that the use of infinitesimals as a process is wrong and poses logical and epistemological problems, making them impossible to be perceived. Both of them believed that ‘existing’ means ‘capable of being grasped.' In spite of their criticism of referring to infinitesimals as a process, their solution to the problem was completely different. Berkeley sacrificed mathematics and science on the altar of epistemology and theology, while Robinson refused to give up anything; he wanted it all: epistemology, mathematics and theology, a goal which he achieved using rigorous logic in his construction of non-standard analysis.