When I finished my PhD 15 years ago, the neurosciences defined the main function of brains in terms of processing input to compute output: “brain function is ultimately best understood in terms of input/output transformations and how they are produced” wrote Mike Mauk in 2000 (DOI: 10.1038/76606). Since then, a lot of things have been discovered that make this stimulus-response concept untenable and potentially based largely on laboratory