The whole of Broussais’s physiology is founded upon irritation. He says, “Irritation constitutes the basis of the physiological doctrine.”[181] But what is irritation? Broussais replies: “It is the exaggeration of contractility.”[182] But then, what is contractility?
In Haller, the term irritability (for that is his term for contractility) possesses a precise meaning and import. Irritability is a property of muscular fibre, by which it shortens or contracts itself when touched.
Haller demonstrated, and it is his glory, that the muscle alone moves when it is touched. What is that to Broussais? He goes back again to the vague irritability of Glisson and de Gorter: like those authors, he assigns it to every tissue, and, like them, he explains every thing by means of it.
Broussais’s irritation is merely Haller’s irritability exaggerated and deformed.
The genius of Broussais was too impatient to allow him to proceed step by step up to the idea—too impassioned to hinder him from being satisfied with the name—and for that very reason he appears to have been by nature fitted for success in a school where the name is every thing.
But here is the great difference. Gall and Broussais laboured for the School: Descartes toiled for the human mind.