Stage Directions and Thematic Symbolism in 'The Glass Menagerie'

In the play 'The Glass Menagerie' by Tennessee Williams, the stage directions provide key insights into memory, character dynamics, and the fragile nature of the setting. In a particular scene, the stage is described as being 'dimly lit, with a single spotlight on the table where the glass figurines are displayed, representing both beauty and fragility.' How do these stage directions enhance the audience's understanding of the play's themes?