mind to be reliable consistently, as in, for example, Descartes's idea of clear and distinct perceptions). According to Augustine, illumination is obtainable to all rational minds and is different from other forms of sense perception. It is meant to be an explanation of the conditions required for the mind to have a connection with intelligible entities. Augustine also posed the problem of other minds throughout different works, most famously perhaps in On the Trinity (VIII.6.9), and developed what has come to be a standard solution: the argument from analogy to other minds. In contrast to Plato and other earlier philosophers, Augustine recognized the centrality of testimony to human knowledge and argued that what others tell us can provide knowledge even if we do not have independent reasons to believe their testimonial reports. Just war Augustine asserted Christians should be pacifists as a personal, philosophical stance. However, peacefulness in the face of a grave wrong that could only be stopped by violence would be a sin. Defence of one's self or others could be a necessity, especially when authorized by a legitimate authority. While not breaking down the conditions necessary for war to be just, Augustine coined the phrase in his work The City of God. In essence, the pursuit of peace must include the option of fighting for its long-term preservation. Such a war could not be pre-emptive, but defensive, to restore peace. Thomas Aquinas, centuries later, used the authority of Augustine's arguments in an attempt to define the conditions under which a war could be just. Free will Included in Augustine's earlier theodicy is the claim God created humans and angels as rational beings possessing free will. Free will was not intended for sin, meaning it is not equally predisposed to both good and evil. A will defiled by sin is not considered as "free" as it once was because it is bound by material things, which could be lost or be difficult to part with, resulting in unhappiness. Sin impairs free will, while grace restores it. Only a will that was once free can be subjected to sin's corruption. After 412, Augustine changed his theology, teaching that humanity had no free will to believe in Christ but only a free will to sin: "I in fact strove on behalf of the free choice of the human 'will,’ but God's grace conquered" (Retract. 2.1). The early Christians opposed the