Olaf Müller’s book (More Light) develops a new case for
underdetermination (prismatic equivalence), and, as he is
focusing on theories of a ‘limited domain’, this assumes the
containability of the theories. First, the paper argues that
Müller’s theory of darkness is fundamentally Newtonian, but
for Newton’s optical theory the type of theoretical structure
Müller adopts is problematic. Second, the paper discusses
seventeenth-century challenges to Newton (by Huygens and
Lucas), changes in the proof-structure of Newton’s optical
theory, and how these affect Müller’s reconstruction.
Müller’s book provides empirically equivalent theories, yet
the historical theories were not empirically equivalent, and
the same experiments were used to extract different bodies of
evidence to rebut the opponent. Third, Goethe’s multi-layered
critique of Newton’s experimental proof is investigated,
including his developmental account of prismatic colours, the
role of experimental series in rejecting Newton’s
observations, and his incorporation of the ‘limited domain’
of prismatic colours in a broader framework. Two key elements
of Goethe’s method, polarity and strengthening are discussed
in contrast to Müller, who only utilises polarity in his
account. Finally Neurath’s attempts to come to grips with the
optical controversies and the prism-experiments with ‘blurred
edges’ are recalled. Müller also discusses in detail some of
these experiments and heavily draws on Quine. Neurath
developed Duhem’s and Poincaré’s conventionalist insights and
had good reasons to be pessimistic about theory-containment.
Their differences provide some additions to the history of
the Duhem–Quine thesis
