And I would add one last comment: Lear ends with the implication that nature lacks a reason, that perhaps the universe lacks rational meaning in spite of our attempts to infuse it with such. That, perhaps, is the significance of Cordelia's death: the play could end satisfactorily without that, but no, she dies, apparently for no real reason. Critic Frank Kermode calls this Shakespeare's cruelest play for that very reason--that Shakespeare posits a universe that lacks moral justification for events. For that reason, many critics find it is the most relevant of Shakespeare's play for the 20th and 21st centuries, in the aftermath of the holocaust, genocide, and constant war.
To expound on the previous post, for the noble characters in the play, namely Kent, Gloucester, the Fool, Cordelia, and Edgar, the ‘Reason’ of the ‘natural’ world order is to remain loyal to and preserve the orthodox view of ‘nature,’ (which maintains that the established social order should be respected and maintained) regardless of the suffering they must endure. There is a contrasting theory of ‘Reason’ of the ‘natural’ world orderi n the play however. For the evil characters, namely Regan, Goneril, Cornwall, Oswald, and Edmund, the ‘Reason’ is to destroy the ‘natural’ world order. These characters wish to topple the orthodox hierarchy, using whatever means necessary, and place themselves atop a new one.
Of course, the storm that rages during the play, with Lear himself caught in it, is a physical manifestation of nature itself raging against this upheavel.
The two views in Lear are survival of the fittest, and a predetermined (by God) social order. God's plan, was basically that each person was chosen by God in the social hierarchy. Kings above his subjects, men ahead of women, etc. To protest this order, would seem to go against God. Survival of the fittest basically means that those who are physically able, or crafty, rise above the rest.