Conversation so far:
Where did William Cullen receive medical training?
William Cullen began medical training as apprentice to John Paisley, a Glasgow apothecary surgeon, then spent 1729 as surgeon on a merchant vessel trading between London and the West Indies.
Where did William Cullen teach?
In Glasgow, William Cullen gave extramural lectures for the University, on physiology, botany, materia medica, and chemistry.
When did William Cullen write his book, First Lines of the Practice of Physic?
William Cullen's best known work, First Lines of the Practice of Physic, was published in a series of editions between 1777 and 1784.
How was William Cullen's book, First Lines of the Practice of Physic received?
How was William Cullen's book, First Lines of the Practice of Physic integral to the Scottish Enlightenment?
In the 18th century, a period of Scottish Enlightenment, there were competing theories about the mechanisms of the human body and the causes of diseases proposed by different professors.

Question: what did he say about the nervous system?
Self-contained rewrite: What did William Cullen say about the nervous system?