 The previous section was devoted to the issue of how to devise a conceptual analysis of dispositions in an attempt to improve our understanding of dispositions. Another way of improving it is to identify characteristics that distinguish dispositions from non-dispositional properties, especially, ‘categorical properties’. What are categorical properties? With respect to this question we are in no better position than we are with respect to dispositional properties. There are some clear cases like roundness and having two arms. But it is not clear what characteristics they have in common. See Mumford 1998, pp, 20–22; Bird 2007a, pp. 66–67, 2013; Ellis 2010; Yates forthcoming for some attempts to characterise categorical properties. (Note that hybrid properties—like the property of being soluble and round—are possible (McKitrick 2003b, footnote 9). We’ll ignore them.) 