Off-campus UMass Amherst users: To download campus access dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.

Non-UMass Amherst users: Please talk to your librarian about requesting this dissertation through interlibrary loan.

Dissertations that have an embargo placed on them will not be available to anyone until the embargo expires.

Author ORCID Identifier


Open Access Dissertation

Document Type


Degree Name

Doctor of Philosophy (PhD)

Degree Program


Year Degree Awarded


Month Degree Awarded


First Advisor

Ned Markosian

Second Advisor

Phil Bricker

Third Advisor

Maya Eddon

Fourth Advisor

Ana Arregui

Subject Categories



Contemporary metaphysics is dominated by the view that every object belongs to a kind permanently in the sense that it cannot cease to belong to that kind without thereby ceasing to exist. For example, some philosophers think that a person is destroyed if they cease to be a person, a statue is destroyed if it ceases to be a statue, and so on.

I believe that this standard view is false. Being a person, or a statue, or etc., is like being a child: just as I did not cease to exist when I ceased to be a child, so people and statues need not cease to exist when they cease to be people and statues. Borrowing a term from Daniel Korman (who uses it in a similar but perhaps not identical way), I call this view phasalism because it entails that the kind-properties which ordinary objects instantiate are phase sortal properties, i.e., kind-properties that an object can instantiate for a temporary phase of its career.

This dissertation is a partial defense of phasalism. I develop a phasalist metaphysics in detail, highlighting its virtues and rebutting objections along the way. After some stage-setting (Chapter 1), I defend a phasalist criterion of identity over time for ordinary objects (Chapter 2), as well as a phasalist account of the role that sortal properties play in the identity over time of ordinary objects (Chapter 3). Then I defend a phasalist-friendly approach to the identity over time of lumps, hunks, pieces, etc. of matter (Chapter 4). The material in these chapters amounts to a phasalist solution to certain material coincidence puzzles, such as the puzzle of the statue and the piece of clay. I go on to show that familiar puzzles about undetached parts (Chapter 5) and fission (Chapter 6) can be solved within the confines of my phasalist metaphysics as well.


Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

Available for download on Saturday, May 13, 2023

Included in

Metaphysics Commons