The research project takes up two main aims. The first is to explore the theoretical underpinnings
of, and relations between, the necessity and proportionality conditions of just war theory. Briefly,
necessity says that a war (or action in war) is only permissible if it is the least harmful option for
securing some moral good; e.g. if a moral good can be secured by trade sanctions, then war is
impermissible *w.r.t. the necessity constraint*. Proportionality says that a war (or action in war) is
only permissible if it secures more good than bad; e.g. if a war to halt genocide will kill more
innocents than it saves, then it is impermissible *w.r.t. proportionality*. Examining the theoretical
underpinnings of these constraints is crucial, because they are universally agreed on, are codified
in many legal and military texts, but are poorly understood, and difficult to systematically employ
in actual combat situations.

The second aim of the project is to formulate necessity and proportionality in formal logical terms,
so that they can be more easily engaged with, and so that their underlying structure can be made
more clear. This will further add to the clarity of our understanding of these concepts, and further
illuminate how they relate to each other (as well as how they may relate to other just war criteria).
In developing these concepts in formal logical terms, it will also be possible to examine how they
are affected by our modal understandings of time, ability, or agency.