Abstract
Colemanand Shapiro have recently advanced a second at-
tempt to reconcile Hart’s practice theory of rules and the idea of
the normativity of law; i.e., the idea that legal rules qua social
rules give reasons for actions and, in some circumstances create
and impose duties and obligations. Their argumentative strategy
is to resort to elements in Bratman’s work on shared agency and
planning, though they introduce important and substantive
modifications to Bratman’s own explanation. Bratman
describes his own theory as a modest theory of the will where the
notion of planning plays a fundamental role. Both Shapiro’s and
Coleman’s application of Bratman’s planning theory of agency
to an authority structure such as law is impressive, but a number
of objections can be levelled, with the intention of grasping both
the nature of authority structures and the normativity of law.
Although I have referred to Shapiro’s and Coleman’s applica-
tions as being similar to one another, the differences are sub-
stantive and important. I will scrutinise both Shapiro’s and
Coleman’s explanations of ‘shared agency’ and discuss the
objections that can be raised against each application.