The problem of justification of the almighty and perfect Creator in the face of the fact that there is evil in the world was posed as early as the 3rd century BC by Epicureans and Stoics. The author of the article uses St. Thomas Aquinas’ and G.W. Leibniz’s philosophical inspirations to demonstrate by means of formal-logical means that inferring non-existence of evil from existence of God, as well as non-existence of God from existence of evil is a logical error. The analysis begins with the theory of an omniscient, infallible and omnipotent being, identified with God. “Will”, “allowance” and “objection” with respect to facts are differentiated and the law of logical squares with respect to acts of will and the iteration of states of God’s ...