Abstract
Throughout his work Aquinas is consistent in holding that, about God, we do not know what He is but rather what He is not. We do not have a direct knowledge of divine essence in this life. However, from his De potentia onwards, and in the Summa theologiae , Thomas argues that the names which mean divine perfections –being, goodness, wisdom and the like– are not merely negative or relational terms, but are predicated substantialiter of God. That means they signify the very divine substance, though imperfectly. The paper tries to analyze what type of knowledge this attribution presupposes, and according to this, to what extent his natural theology can be assessed as negative or positive