Jonathan Swift assigns cardinal virtues like friendship, benevolence etc.to the houyhnhnms . What lesson does he want to give to his readers through this?

A species of horses who are endowed with great kindness and virtue. Gulliver lives among them for several years and afterwards is extremely reluctant to return to England. Swift uses the Houyhnhnms to reflect just how far away human nature and English culture are to enlightenment. Gulliver feels returning to England is like returning to the dark ages. The reader gets the sense of just how amoral and uncivilized humanity actually is.