Figes exercises her feminism by showing in minute, ofttimes silent, detail the subordinate role of women's lives in a world dominated by men's personalities and expressions. In Light, this is in part accomplished through insight into women's and children's contemplations and introverted musings about experience.
Everyone in Monet's inner circle, especially Alice, is subjugated to his obsession to create great art. Alice feels alienated from him, and he doesn't seem to particularly care that he is alienated from her. Ultimately, Figes is asking exactly what art is worth, and wondering to what extent it can reflect life. As for feminism and Marxism, the relationship between Alice and Monet conforms to the patriarchal lines that one might attribute to the bourgeoisie.
Monet's disinterest in his familial problems is a sign of his immaturity; like his daughter, Lily, Monet is far more interested in the moment instead of the continuing future. Everyone around him is hyper-aware of the future, since their actions will have an affect on everything in life; Lily, and to a certain extent Monet, are happy with the "now," understanding in a childish way that the world exists for their pleasure and larger problems are beyond their ability to empathize with or fix.
I suppose one essential theme within the humanities that we can focus on in this text is the value of art and the impossibility of ever seeking to recreate it in its entirety. Monet's fevered attempts to capture reality on his canvases are shown to be futile, and leads to him becoming detached from the world and the reality around him.