The Swing Lemma, proved by G. Grätzer in 2015, describes how a congruence spreads from a prime interval to another in a slim (having no M3\documentclass[12pt]{minimal}
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\begin{document}$$\mathsf {M}_{3}$$\end{document} sublattice), planar, semimodular lattice. We generalize the Swing Lemma to planar semimodular lattices.