How did Wagner combine leitmotifs in Tristan und Isolde?

In Tristan und Isolde, Richard Wagner utilized leitmotifs as a core element of his musical structure, employing them to provide psychological insight and reinforce dramatic action.1

Wagner combined these leitmotifs by setting them in counterpoint against one another. This technique allowed the orchestra to balance the vocal "speech-song" (Sprechgesang) while simultaneously interweaving the leitmotifs to create a dense, symphonic fabric. By layering these themes, Wagner achieved a "counterpoint" of connotations and emotions, where the musical interaction of the motifs mirrored the complex dramatic developments on stage. While some motifs, such as the three-note death theme, functioned primarily through allusion, the contrapuntal combination of these themes ensured that the music remained cohesive and intellectually rich throughout the drama.21