What intrigued me about plasticity was that it was not yet tamed into something consistent: my fieldwork unfolded in a situation in which the old truth of cerebral fixity had already been dissolved by plasticity—but plasticity had not yet been stabilized. It still could be many different, in part mutually exclusive, things. To me, it was a bit as if the brain—and along with it the human—had been released from a form of knowledge that claimed to exhaust it. It was as if the brain and the human as constituted by the brain had broken free.
The big theme of the book is of course how the discovery of plasticity upset the classical concept of the brain as a fixed and immutable structure. But there is no overall core argument that would organize and arrange the stories assembled in Plastic Reason. In fact, I could say that one of the major points of Plastic Reason is precisely to not have a core argument.