LitCharts assigns a color and icon to each theme in King Lear, which you can use to track the themes throughout the work.
Fathers, Children, and Siblings
Authority and Order
Disintegration, Chaos, Nothingness
Old Age
Fooling and Madness
Blindness and Insight
Summary
Analysis
Cordelia, attended by the Gentleman from 4.3 and a Doctor sends out a search party of one hundred soldiers for her father, who, she has heard, is raving "mad as the vexed sea" (4.4.2). She then promises the doctor that whoever cures Lear can have everything she owns. The doctor responds that, in order to be cured, the mad king needs rest.
Clearly concerned for her father, and prepared to give up anything to restore him, Cordelia proves that she places utmost importance on her duties as a child, setting them before wealth or political power.
A messenger enters with news that the British are marching on the French camp. Cordelia responds that she is aware, explaining that the whole purpose of France's war on England is to avenge her father: "No blown ambition doeth our arms incite,/ But love, dear love, and our aged father's right" (30-1).
As the British army approaches, the face-off between the self-interested children (Edmund, Goneril, and Regan) and the selfless Cordelia comes to a head.