  Brown's 1971 paper "Admissible estimators, recurrent diffusions and insoluble
boundary value problems" is a landmark in the admissibility literature. It
nearly completely settles the issue of admissibility/inadmissibility for
estimating the mean of a multivariate normal distribution with identity
covariance under sum of squared error loss. We revisit this wonderful tour de
force on its 50th anniversary and present an alternative and more direct proof
of the result for generalized Bayes estimators corresponding to priors which
are a subclass of scale mixtures of spherical normals.
