Menger's theorem can be stated as follows: Let G = (V, E) be a finite graph, and let A and B be subsets of V. Then there exists a family F of vertex-disjoint paths from A to B and a subset S of V which separates A and B, such that S consists of a choice of precisely one vertex from each path in F.
Erdös conjectured that in this form the theorem can be extended to infinite graphs. We prove this to be true for graphs containing no infinite paths, by showing that in this case the problem can be reduced to the case of bipartite graphs.
