<br> <a href=../gap/lambdaRL1.html>Lattice of subvarieties of residuated lattices</a> <p> <a href=../gap/lambdaL.html>Lattice of subvarieties of lattices</a> <p> Does the lattice of subvarieties of residuated lattices have any coatoms? Is <b>RL</b> join-irreducible? <p> <a href=../gap/index.html>Lists of finite algebras</a> (36) (58) <p> <b>Theorem (Dilworth 1939):</b> Let `X` be a set of elements in a residuated lattices that pair-wise join to `e`. Then `X` generates a generalized Boolean lattice under `vv,^^`. <p> Find effective ways to compute in finitely presented algebras. <p> <a href=../gap/lambdaRL3.html>Implications between identities</a> <p> <a href=../logic/theoriesPO1.html>Interpretability</a> <p>   <p>   <p>   <p> <center> <img src=Robert_Dilworth1.jpg> <p> <img src=Robert_Dilworth2.jpg> </center>