Freedom therefore consists in the control over ourselves and over external nature, a control founded on knowledge of natural necessity
The film begins with Eiji Okada walking confidently over the desert, hunting for insects, master of his surroundings. He wishes to make advances in science, and have his name live on by finding a new type of bug. Nature gets the better of him, however. Forced to shovel sand and robbed of modern comforts, his horizons shrink. At the end of the film, he abandons bugs for experiments with a reservoir, a more pressing concern for the people around him. He finds freedom not in the opportunity to go home, but in helping the community who have exploited him.
That's about as far as that reading takes us, so let's try another, existentialist angle. Freedom as the ability to pursue a life project of your choosing, a freedom the Woman of the Dunes cannot have, being cloistered in a shack sinking into the ground. Shoveling sand gives the Woman purpose – she is happy to be boxed in. For her guest, this is intolerable. While she digs for the bones of her family and clings to the old community spirit, he wants to escape and be famous – private and public spheres clearly delineated. Not only that, but the woman is effectively prostituted by the people around her. She is capable of genuine affection, perhaps, but it's moulded heavily by the demands of the men she serves. Those sexual demands prove to be her downfall. She has almost no subjectivity at all, being an automaton used and discarded by the powerful.
Marx does come in through another angle: the dialectic. The Woman of the Dunes can be said to be at one with nature and her fellow man – being oblivious about her exploitation, completely submissive towards the men around her, and having very simple goals (preserving the group – even the radio is justified as being for someone else's happiness). Her guest on the other hand feels the full weight of his alienation. But in living with the Woman of the Dunes, some of that old community spirit rubs off. He stays even when he doesn't have to, his labour given freely to assist his fellow men according to their needs. And that transformation is not achieved through revolution, but through something resembling love and sacrifice.
And finally, a reading through Lovecraft. The two main characters in this film are reduced to insects burrowing in the sand, as if they were observed in close-up by an alien intelligence watching their equivalent of a nature documentary. This audience only dimly perceives the difference between living and dead matter – its interest divided equally between the shifting sands and the human drama playing out around them. There is a kind of existentialist terror to all this – men and women scrabbling over the face of the earth, their stories as cosmically significant as a boulder of sand.
Have I reduced the film enough? That initial review is right in that a film so symbolically rich as Woman of the Dunes lends itself to multiple responses. But there's nothing wrong with cataloguing a few, right?