Full Idea
Nothing in the natural world seems to be more obscure and difficult to grasp than the prime matter of things.
Gist of Idea
Prime matter is exceptionally obscure
Source
Jacob Zabarella (De rebus naturalibus [1590], I.1 col 133), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 2.1
Book Reference
Pasnau,Robert: 'Metaphysical Themes 1274-1671' [OUP 2011], p.17
A Reaction
This spells the beginning of the end for 'prime matter', since a late scholastic is doubting it, even before the scientists got to work. Most modern Aristotelians slide quietly past prime matter, as unhelpful.