formal-system public under concept 1247 List Picture As a command %3 n0 formal-system n2 finite-automaton n0->n2 n3 formal-grammar n0->n3 n4 classical-logic n0->n4 n5 description-logic n0->n5 n6 lambda-calculus n0->n6 n7 modal-logic n0->n7 n8 propositional-logic n0->n8 n9 type-theory n0->n9 n1 concept n1->n0