Apodictic judgments are clearly provable or logically certain. Conversely, a deductive system is complete if every logically valid formula is derivable. Computational models require a mathematically and logically formal representation of a problem. Thus they were committed to values that could not logically be reconciled. Leibniz creates an argument that flows smoothly and logically from point to point. In propositional logic, there is no distinction between a tautology and a logically valid formula. Participants are told to only agree with conclusions that logically follow from the premises given. In one sense it is irrefutable and logically true. Hume, I felt, was perfectly right in pointing out that induction cannot be logically justified. This logically rigorous approach essentially equates indefinite remission with cure. To be logically correct, some restrictive assumptions are needed. They result in four kinds of opposing assertions, each of which is logically valid. This demonstrates the fact that formula 5 is logically equivalent to formula 6. They may feel guilty over things that logically should not cause guilt. The second and third riddles reinforce the expectation for this logically absurd structure.