Composition as Identity and the Innocence of Mereology

According to the thesis known as ‘Composition as Identity’ (‘CAI’), every entity is identical to the parts it fuses. Many authors in the literature acknowledge that, in spite of its controversial character, one attractive virtue of CAI is its apparent ability to give a straightforward account of the innocence of mereology. In this paper I will present a simple argument according to which CAI entails that no composite entity can be said to be ontologically innocent in the relevant sense. After having shown that said argument is independent from the problems surrounding the infamous ‘Collapse Principle’, I will conclude that CAI-theorists should endorse a suitably ‘restricted’ version of CAI. In the final part of the paper I will then argue that the best restricted version of CAI is the theory according to which every composite entity is identical to the plurality of its atomic parts.