 Again, this principle is stronger than (P.4a) and (P.4b), since it rules out all patterns in Figure 2, and in M it is equivalent to (P.4). Indeed, (P.4d) says, literally, that if something has a proper part, then it has at least two disjoint parts, which Simons (1987: 27) takes to express the same intuition captured by (P.4). Yet (P.4d) is logically weaker than (P.4), since it admits the non-antisymmetric model in Figure 3, middle, and for that reason it may be deemed more suitable in the context of theories that violate (P.3). Note also that (P.4d) does not admit the symmetric model on Figure 3, left, so in a way it is stronger than (P.4c). In another way, however, it is weaker, since it admits the model in Figure 3, right, which (P.4c) rules out (and which someone who thinks that, say, the clay is part of the statue, but not vice versa, might want to retain).