"The manner in which Cicero addresses himself to the task of refuting the Stoics, shows that he did not think he could effect anything against them in argument unless he had first demolished divination. And this he attempts to accomplish by denying that there is any knowledge of future things, and maintains with all his might that there is no such knowledge either in God or man, and that there is no prediction of events." -Augustine (De Civitate Dei, 5.9)
There you have it. Cicero was an open theist. How very ironic that the modern day proponents of this aberrant theological view- who accuse classical theists of being more influenced by Greek and pagan philosophy than by the scriptures- should have as their chief theologian in antiquity, not a church father, but a pagan!