Ruelle's "heuristic theory of phase transitions" ([Comm. Math. Phys., Volume 53, Number 3 (1977), 195-208](https://projecteuclid.org/euclid.cmp/1103900700))  turned out to be false in certain Banach spaces of interactions: see my "Generic triviality of phase diagrams in spaces of long-range interactions" ([Comm. Math. Phys., Volume 106, Number 3 (1986), 459-466](https://projecteuclid.org/euclid.cmp/1104115783)).