winston mereology taxonomy

More than the sum: Understanding relationships between parts and wholes

| Parts, wholes, and relationships |

In a paper on meronymic relationships, researchers described three dimensions and six specific types of part-whole relationships. Their descriptions provide terminology for comparing and contrasting the various ways parts and wholes can be related. Although emergence/cause and effect is not identified as its own type, it is most accurately characterized as a feature/activity relation.

The differences among the six types of meronymic relations are indicated by the values of three relation elements which summarize characteristic properties of the relations. Meronymic relations differ in three main ways: whether the relation of part to the whole is functional or not, whether the parts are homeomerous or not, and whether the part and whole are separable or not. Functional parts are restricted, by their function, in their spatial or temporal location. For example, the handle of a cup can only be placed in a limited number of positions if it is to function as a handle. Homeomerous parts are the same kind of thing as their wholes, for example, (slice-pie), while nonhomeomerous parts are different from their wholes, for example, (tree-forest). Separable parts can, in principle, be separated from the whole, for example, (handle-cup), while inseparable parts cannot, for example (steel-bike).

winston mereology taxonomy


Winston, M. E., Chaffin, R., and Herrmann, R. (1987). A taxonomy of whole-part relations. Cognitive Science (11), 417-444.