He has plenty of grey matter, but he lacks common sense.
У него много серого вещества, но ему не хватает здравого смысла.
Definitions
Grey matter refers to regions of the brain and spinal cord that are primarily made up of neuronal cell bodies, dendrites, and unmyelinated axons, as opposed to white matter, which consists mainly of myelinated axons. Grey matter is involved in muscle control, sensory perception, memory, emotions, and decision-making.
