  We argue here about the relevance and the ultimate unity of the Bayesian
approach in a neutral and agnostic manner. Our main theme is that Bayesian data
analysis is an effective tool for handling complex models, as proven by the
increasing proportion of Bayesian studies in the applied sciences. We disregard
in this essay the philosophical debates on the deeper meaning of probability
and on the random nature of parameters as things of the past that do a
disservice to the approach and are incomprehensible to most bystanders.
