txtDefinition=The {\uldb section}{\v 95736} in a {\uldb sonata form}{\v 96905} that introduces the principal {\uldb thematic}{\v 99088} material of the {\uldb movement}{\v 151907}, analogous to the introduction of characters in a novel. Its four normative stages commence from stability ({\uldb primary area}{\v 93113}), move through instability ({\uldb transition}{\v 101441}), and arrive at temporary stability ({\uldb secondary area}{\v 95388} and {\uldb closing area}{\v 77711}).
