  The classic question of a nonabelian Yang-Mills analogue to electromagnetic
duality is here examined in a minimalist fashion at the strictly 4-dimensional,
classical field and point charge level. A generalisation of the abelian Hodge
star duality is found which, though not yet known to give dual symmetry,
reproduces analogues to many dual properties of the abelian theory. For
example, there is a dual potential, but it is a 2-indexed tensor $T_{\mu\nu}$
of the Freedman-Townsend type. Though not itself functioning as such,
$T_{\mu\nu}$ gives rise to a dual parallel transport, $\tilde{A}_\mu$, for the
phase of the wave function of the colour magnetic charge, this last being a
monopole of the Yang-Mills field but a source of the dual field. The standard
colour (electric) charge itself is found to be a monopole of $\tilde{A}_\mu$.
At the same time, the gauge symmetry is found doubled from say $SU(N)$ to
$SU(N) \times SU(N)$. A novel feature is that all equations of motion,
including the standard Yang-Mills and Wong equations, are here derived from a
`universal' principle, namely the Wu-Yang (1976) criterion for monopoles, where
interactions arise purely as a consequence of the topological definition of the
monopole charge. The technique used is the loop space formulation of Polyakov
(1980).
