In his exquisitely layered seventh feature, Possible Love (Ga-neung-han sa-rang), Lee Chang-dong’s humanistic observational skills remain at their peak, the acuity of his insights into emotional lives and social conditions unparalleled. More straightforward though no less affecting than the haunting ambiguities of his last film, Burning, the Korean director’s melancholic new work turns his customary slow-burn approach to the simmering tensions between two couples from different economic strata. A profound meditation on trauma, loss of dignity, yearning and class envy, this is a sad but beautiful chamber piece, fleshed out by a…