Two strikingly contrasted Balanchine ballets compose this program. The Four Temperaments, a staple of the neoclassical Black & White repertory, changes moods, styles, and tempos as it emphasizes four different elements of the human psyche. Liebeslieder Walzer, danced to the Brahms songs of the title, performed by singers at the side of the stage, evokes a night of romantic magic as four couples move from formal ballroom dance to a mysterious nether realm where the couples’ untethered souls collide and tangle and unite.