The \"unbearable lightness\" in the title also refers to the lightness of love and sex, which are themes of the novel. Kundera portrays love as fleeting, haphazard and possibly based upon endless strings of coincidences, despite holding much significance for humans.
Tereza: I know I'm supposed to help you, but I can't. Instead of being your support I'm your weight. Life is very heavy to me, but it is so light to you. I can't bear this lightness, this freedom... I'm not strong enough.
He was fifty then, and had settled, not into a family or a lucrative career, but into this lightness. He preached to me the virtues of having little, living simply, of being free of the ties that bind, and I never thought, free of a daughter. He told me that he was happy this way.
Mr. Kundera says Sabina lives by betrayal, abandoning family, lovers and, finally, country, in a way that condemns her to what he calls a ''lightness of being,'' by which he means a life so lacking in commitment or fidelity or moral responsibility to anyone else as to be unattached to the real earth. By contrast, his fourth character, Tereza, the loyal wife of Tomas, suffers an unflagging love for her philandering husband that finally is responsible for his ruin, because it's her unwillingness to live in exile that brings him back to his fate in Czechoslovakia after he has set himself up nicely in a Swiss hospital. Thus, Tereza, the exact opposite of Sabina in commitment and fidelity and rootedness to the real earth, sinks under an unbearable moral burden, weight and lightness, in the Kunderian physics, adding up to the same thing.
Whether personal or political, all attitudes, stands, positions in the Kunderian vision come up short. He will kill off three of his quartet and allow the fourth to disappear from the book, presumably from a lightness of being; but his true story, the one to which he gives honest service, is the operation of his own mind as it formulates and finds images for the disastrous history of his country in his lifetime. The paradox of the essential identity of opposites describes an intractable world in which human beings are deprived of a proper context for their humanity. The author who ostentatiously intrudes in his characters' lives and tells them how to behave mimics, of course, the government that interferes deeply in its citizens' lives and tells them how to behave. Tomas and Sabina and Franz and Tereza were invented to live under two tyrannies, the tyranny of contemporary Czechoslovakia and the tyranny of Mr. Kundera's despair. 1e1e36bf2d