[please see the plot of Lagaan at Wikipedia] That which divided the castes - untouchability - is overcome by the persuasive arguments of the hero of "Lagaan." As a result, tremendous energy is released thereafter that unites them all for an eventual victory over their oppressors, the British team. We see here how Nature works on multiple problems simultaneously -- overcoming the internal caste system of the Indians, and overcoming the external oppression of the British. H