<p>I develop a theory of naturalness according to which properties are natural relative to categories of objects. This new theory avoids a problem that, I argue, afflicts standard theories: whereas standard theories allow for only one ordering of properties, considerations of the similarity and dissimilarity made by some negative properties—like <i>having no parts</i>, <i>having no members</i>, <i>having no determinate mass</i>, <i>reflecting no visible light</i>—require admitting more than one. Additionally, I argue that my view accounts for genuine categories, category mistakes, and negation as privation, and that it accounts for a distinction between characterizing and non-characterizing fundamentality.</p>