 Another very interesting logic is Neil Tennant’s Core Logic. One of the “fallacies” that relevance logic was created to avoid is ex falso quodlibet, or explosion – the inference from a contradiction to any proposition whatsoever. C.I. Lewis justified explosion by means of a little argument. He started with the premise \(p \amp \neg p\). By conjunction elimination he derived, \(p\), and by disjunction introduction, \(p\vee q\). From the premise, he also derived \(\neg p\), by conjunction elimination. Thus, he had \(p\vee q\) and \(\neg p\). From these, by disjunctive syllogism, Lewis derived \(q\). Mainstream relevance logicians block this argument by rejecting disjunctive syllogism. The rejection of disjunctive syllogism, however, has become one of the most controversial aspects of relevance logic.