casuistically

Using casuistry or casuistics.

He approached the moral dilemma casuistically, not abstractly from first principles.

From the perspective of casuistics or casuistry.

Those ideals are casuistically the best whose realisations lead to least number of other ideals sacrificed.

Rule-utilitarian arguments — arguments that proceed from the consequences of our moral rules rather than of our individual acts — are casuistically very powerful.