I was awarded my PhD from the Australian National University in December 2013. My dissertation was called The Scope of Dependence-based Duties. The basic thought was that if you are dependent on someone in the right way, then that person has a moral duty. We can call this a “dependence-based duty.” The dissertation explored the scope of these duties—the range of normative assertions they produce—in both individual and group ethics.

Part I built a theoretical framework for these duties. I started by developing what I called the “Dependency Principle,” which gives us an ecumenical account of when these duties arise for agents acting independently of others. Roughly, they arise when three conditions are met: (1) the agent is sufficiently likely to fulfil an important interest if she takes her most efficacious measures for doing so; (2) the cost of those measures is below some threshold; and (3) the cost of those measures is no higher than that of any other agent’s most efficacious measures for fulfilling that interest.

This is relatively straightforward for individuals—but some of the most pressing dependence-based duties seem to be held by groups. I gave an account of group agents’ capacities to bear duties, before arguing that the Dependency Principle cannot capture the full range of moral duties that arise out of our dependence on groups. Specifically, it cannot capture cases where no group agent exists, but where a number of individuals could mutually respond to one another to fulfil an important interest, or could come to constitute a group agent that would (if it existed) bear a duty under the Dependency Principle. For these cases, we need a “Coordination Principle” in order to capture all the dependence-based duties that common sense tells us exist. Thus, it was my argument that there are two distinct types of dependence-based duties: one derived from the “Dependency Principle” and the other from a separate “Coordination Principle.”

I then drew out some important implications of the Dependency and Coordination Principles, within interpersonal and international ethics. Part II considered a case from interpersonal ethics. I argued that my two dependence-based principles together provide a unified explanation of the moral theory of care ethics—the result being that care ethics is more systematised than its proponents often claim, and that the dependence-based principles gives us a wider range of claims about interpersonal ethics than first meets the eye. This part of the dissertation later evolved into my first book, The Core of Care Ethics. In Part III, I turned to a case from international ethics. I argued that the Dependency and Coordination Principles together give a unified explanation of the international political doctrine of the Responsibility to Protect—the result being that we can more neatly assign the duties of this doctrine than had hitherto been recognised.

By seeing that the Dependency and Coordination Principles provide a grounding for the claims of care ethicists and Responsibility to Protect proponents, we can see dependence-based duties as potentially underpinning many more normative assertions in interpersonal and international ethics than is commonly imagined.

It’s a shame to spend three-and-a-half years writing something that only two people will ever read. So if you’d like to do me a supererogatory and time-consuming kindness, you could read the dissertation.