Henri Poincaré, ciência e materialismo: o papel das hipóteses na oscilação entre atomismo e continuísmo

This article was produced as an introduction to a Portuguese translation of an article by Henri Poincaré titled "The new conceptions of matter". The aim of this introduction was to shortly summarize Poincaré's scientific and philosophical production, to approach the circumstances on which the text was originally presented and, finally, to analyze the relationship - or the lack of it - that Poincaré establishes between science and materialism.