Once you enlist the full power of the ZFC system, this particular result does become provable. But Friedman has since started to work on more general forms of networks and obtained stronger results . "I have the beginning of a structure theory [for aspects of certain networks] in which there are theorems that can only be proved using some ridiculously strong new axioms," he explains. These axioms go way beyond Peano arithmetic and also ZFC. Whether the undecidable results in question will ever cross the path of applied mathematicians or computer scientists remains to be seen, but given their distinctly computational flavour, the potential is certainly there.