The rippling undercurrent of satire is always there; but it is Chaucer's own peculiar satire--mellow, amused, uncondemning, the most subtle kind of satire, which does not depend upon exaggeration.

The literary critic has only Chaucer's words and his own heart, or sometimes (low be it spoken) his own desire to be original, by which to guide his judgement.

But the historian knows; he has all sorts of historical sources in which to study nunneries, and there he meets Chaucer's Prioress at every turn.
Above all, he has the bishop's registers.
For a long time historians foolishly imagined that kings and wars and parliaments and the jury system alone were history; they liked chronicles and Acts of Parliament, and it did not strike them to go and look in dusty episcopal archives for the big books in which medieval bishops entered up the letters which they wrote and all the complicated business of running their dioceses.

But when historians did think of looking there, they found a mine of priceless information about almost every side of social and ecclesiastical life.

They had to dig for it of course, for almost all that is worth knowing has to be mined like precious metals out of a rock; and for one nugget the miner often has to grub for days underground in a mass of dullness; and when he has got it he has to grub in his own heart, or else he will not understand it.