For, if it is true to say that in essence the tragic hero is intent upon claiming his whole due as a personality, and if this struggle must be total and without reservation, then it automatically demonstrates the indestructible will of man to achieve his humanity. The possibility of victory must be there in tragedy. Where pathos rules, where pathos is finally derived, a character has fought a battle he could not possibly have won. The pathetic is achieved when the protagonist is, by virtue of his witlessness, his insensitivity or the very air he gives off, incapable of grappling with a much superior force. Pathos truly is the mode for the pessimist. But tragedy requires a nicer balance between what is possible and what is impossible. And it is curious, although edifying, that the plays we revere, century after century, are the tragedies. In them, and in them alone, lies the belief--optimistic, if you will, in the perfectibility of man. It is time, I think, that we who are without kings, took up this bright thread of our history and followed it to the only place it can possible lead in our time--the heart and spirit of the average man.
Other possible sources are the anonymous play King Leir (published in 1605); The Mirror for Magistrates (1574), by John Higgins; The Malcontent (1604), by John Marston ; The London Prodigal (1605); Montaigne 's Essays , which were translated into English by John Florio in 1603; An Historical Description of Iland of Britaine (1577), by William Harrison ; Remaines Concerning Britaine (1606), by William Camden ; Albion 's England (1589), by William Warner ; and A Declaration of egregious Popish Impostures (1603), by Samuel Harsnett , which provided some of the language used by Edgar while he feigns madness. King Lear is also a literary variant of a common fairy tale , Love Like Salt, Aarne–Thompson type 923, in which a father rejects his youngest daughter for a statement of her love that does not please him.