This article examines the construction of electronic brain models in the 1940s as an
instance of “working models” in science. It argues that the best way to understand
the scientific role of these synthetic brains is through combining aspects of the “models
as mediators” approach (Morgan and Morrison, 1999) and the “synthetic method”
(Cordeschi, 2002). Taken together these approaches allow a fuller understanding of
how working models functioned within the brain sciences of the time. This combined
approach to understanding models is applied to an investigation of two electronic
brains built in the late 1940s, the Homeostat of W. Ross Ashby, and the Tortoise
of W. Grey Walter. It also examines the writings of Ashby, a psychiatrist and leading
proponent of the synthetic brain models, and Walter, a brain electro-physiologist,
and their ideas on the pragmatic values of such models. I conclude that rather than
mere toys or publicity stunts, these electronic brains are best understood by considering
the roles they played as mediators between disparate theories of brain function
and animal behavior, and their combined metaphorical and material power.
Keywords: models, psychology, cybernetics