According to David Armstrong (1997), all fundamental natural properties are categorical. According to Brian Ellis (2001), this is mistaken, since some properties are essentially dispositional. Brian also thinks that some are categorical and are as David describes them. As regards Brian's first point, I am with him; but I disagree on the second. David is right, all fundamental properties are metaphysically on a par. David is a monist, and so am I; but they are not all categorical, they all have a dispositional character essentially.