This paper proposes a reading of Galileo’s Letter to the Grand Duchess
Christina as analogous to a legal brief submitted to a court en banc.
The Letter develops a theory of the general issues underlying the case
at hand, but it is organized around advocacy for a particular judgment.
I have drawn two architectonic implications from this framework, each
of which helps to resolve an issue still standing in the literature. First, the
Letter anticipates varying degrees of acquiescence to its general account,
and provides ‘hooks’ for different readers to interpret variously while still
converging on the particular judgment. This reading allows for a coherent
Galilean interpretation of passages that notoriously concede priority
to Scripture, while also explaining their dialectical function. Galileo is
neither self-contradictory nor dissimulating here, but strategically leaves
the specification of key distinctions for the reader. Second, the Letter, and
particularly its apparent shifting of the burden of proof, must be understood
in light of the tripartite ‘adversarial-judicial’ framework that Galileo
sets up. The burden of proof is shifted to anti-Copernicans within the
Church, not as a rhetorical trick, but because of the benefits of adversarial
procedure that will accrue to the Church as the responsible judge.