Previously, the author solved the one-, two- and three-dimensional Ising models in the absence of an external magnetic field exactly. Additional convincing proofs for these solutions are given here. The exact solutions of the Ising models in a magnetic field are found. It is shown that the conventional methods of solving the Ising models are incorrect. Heat capacities and zero-field magnetic susceptibilities of the Ising models are calculated exactly for all dimensions (including the case of polonium) and a flaw in Onsager’s solution for heat capacity is detected.
