In "The Canterbury Tales," why do you think the nun is going on the pilgrimage?
Chaucer announces that the nun is the chaplain of the Prioress, but does not take time to describe this nun. One can only assume that she is going on the pilgrimage because she has been asked to by her benefactor, the Prioress. Madame Eglantine (the Prioress) is described as being sentimental and romantic. It is possible that she felt she must have a religious posse with her in order to perform the pilgrimage correctly - somewhat like a superstition.