Deception and lies are what makes King Lear a tragedy. The play is a result, of the consequences triggered off by lies and falsehoods that were told in King Lea's family, as well as in the family of the Earl of Gloucester. In this play, Shakespeare added a sub-plot to the main-plot and both are based on the same events, differing slightly according to the story.
The main-plot involves Lear and his three daughters whereas the sub-plot makes use of Gloucester and his two sons. King Lear gives his daughters a love-test, stupidly intending to measure love with flattery; "Which of you shall we say doth love us most..." (Act 1 Scene 1) Regan and Goneril are full of flattery and nice words and get rewarded, but Cordelia speaks truthfully, refraining from using fancy words; "I return those duties back as are right fit..." (Act 1 Scene 1) Lear fails to see his youngest daughter's honesty and banishes her from his Kingdom, stripping her of every title she had.
Lear and Cordelia
English: Title page of Shakespeare's King Lear (16...
CordeliaShakespeare introduces the theme of 'sight and blindness' with Lear's inability to see Cordelia's truthfulness and his blindness to the false-flattery of his other two evil daughters. Also introduced is the theme of 'Nothing' when Lear tells Cordelia; "How, nothing will come of nothing." (Act 1 Scene 1).
The theme of 'Sight and Blindness' and 'Nothing' reappear throughout the play in many different contexts, but the irony lies in the fact that Lear depicts Shakespeare's theme of sight an blindness by demonstrating that physical sight does not guarantee clear sight and he is left with 'nothing' and becomes 'nothing'.
In the sub-plot, Edgar, like Cordelia who is banished, has to leave, though unlike Cordelia, he is given no chance to prove himself because his brother Edmund cleverly creates the plot...