The notion of matter had been invariably used in philosophical discussions from the High Middle Ages down to early modern times. In this long history of its usage, however, one cannot fail to notice a rather radical semantic shift. What was originally the relational notion of the Peripatetic ὕλη, or Thomist materialitas, which was reserved for the proximate substrate of enmattered phenomena [λόγοι ἔνυλοί], gave way to the absolute notion for the totality of the world as external [res extra me posita], to the point where questioning the existence of matter became equivalent to a skepticism in regards to the existence of a mind-independent world tout court. The following study presents three key moments in this tumultuous historical development of matter, from being a constitutive part of things, to becoming a thing in itself, to be finally reduced to nothing. Accordingly, the arc of this story begins with the popular Renaissance understanding of ὕλη rooted as it was in Aquinas and Averroës and expounded by Alessandro Piccolomini (Chapters I-II); it then segues into the Cartesian matter posited besides the thinking substance (Chapter III); and closes with George Berkeley declaring matter an empty and even contradictory notion (Chapter IV). This developmental story suggests that each thinker, in deciding which aspects of experience he was going to be realist about, was inevitably influenced by the specific theoepistemic values he was operating within. It will become clear that e