GABRIEL CHIAROTTI SARDI

The present thesis aims to compare Louis Pasteur's microbial and Antoine Béchamp’s microzymian theories about the cause of infectious diseases at the end of the 19th century. In short, while Pasteur advocated that diseases were caused by external agents (microbes), Béchamp defended that diseases originated within the organism itself due to an imbalance of certain elementary units (microzymes). The presented question is that many authors stated that Pasteur's ideas stood out in the history of biology for purely political and not epistemological reasons, while Béchamp's theses were more explanatory, although not properly considered in his time. We will seek, through contemporary elements and concepts of the Philosophy of Science, more specifically within the debate about the Inference to the Best Explanation and Scientific Realism, to use epistemological analysis tools to find out which of the two theories is more explanatory and has a greater number of cognitive values ​​or explanatory virtues, pondering, in the end, what are the philosophical consequences of our analysis.