The two previous trilogies in Beethoven's sonata cycle - the three sonatas, Op. 2 and the three sonatas, Op. 10 - both had the third sonata in the group as their focal point and climax. Whether this is the case in the Op. 31 is less certain. On the one hand, Sonata No. 18 is the only one in the opus to be written in four movements, like most of Beethoven's Grandes Sonates (Opp. 7, 22, 26 and 28). On the other, the Sonata is so easy-going, so light-spirited, so full of sunshine, that it feels much more like a release after Tempest's dark tension than a further intensification.
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