Many philosophers and neuroscientists defend a view we express with the slogan that mental science is neuroscience. We argue that there are two ways of interpreting this view, depending on what is meant by ‘neuroscience’. On one interpretation, the view is that mental science is cognitive neuroscience, where this is the science that integrates psychology with the biology of the brain. On another interpretation, the view is that mental science is biological neuroscience, where this is the investigation concerned with the (...) chemistry, physiology and anatomy of neurons and neuronal assemblies. Since the claim about cognitive neuroscience is a scientific triviality, we concentrate on the claim about biological neuroscience, and criticise two initially promising lines of argument for it, one prompted by reflection on the history of biology, and one prompted by reflection on the neurophysiological process known as long‐term potentiation, which may be implicated in learning. We argue that neither of these arguments is successful in supporting the view that mental science is biological neuroscience. (shrink)