Unlike the earlier tagged reference, beast here seems like a joke.

The Knight’s Tale The question of what is the lesser of the two evils seems tobe a running theme in Chaucer’s The Knight’s Tale. This theme is most apparentat the end of part one of The Knight’s Tale when the question is asked ”Yowloveres axe I now this questioun:/ Who hath the worse, Arcite or Palamoun?” (lines1347/48).In other words, it poses the question, what is worse Arcite being exiled andunable to see Emelye or  the positionthat Palamoun finds himself in as a prisoner, but has access to Emelye? I wouldargue that Palamoun’s position is the worse of the two. Arcite, can romanticizethe past or move on in a way that Palamoun is unable to. Palmoun, on the otherhand, is confined in a cell making it difficult to romanticize the past or moveforward.  This idea of the lesser of thetwo evils also appears in lines 1318-23, although not as directly in theprevious lines:Ther as a beest may al his lust fulfille.And whan a beest is deed he hath no peyne;But man after his deeth moot wepe and pleyne,Though in this world he have care and wo.Withouten doute it may stonden so. The answere of thislete I to dyvynys,          In these lines, a beast can act on his desires and can makedecisions without considering an afterlife. However, the opposite is true forman. Chaucer’s use of these juxtapositions to allows him to continue this themeof the lesser of the two evils.What is Chaucer’s intention in having his reader contemplateone side or the other in such a direct way?

The Daily Beast quote is found here.

This is Daily Beast's article about it.

Rebecca Solnit uses this quote perfectly here.

Reference to beasts; what separates us clever beasts from the other beasts?

Uses metaphor to make it seem natural and inborn

Again, rhetoric as what sets humans apart from other animals.