Dialectic. Dialectic, also known as the dialectical method, is a discourse between two or more people holding different points of view about a subject but wishing to establish the truth through reasoned argumentation. Dialectic resembles debate, but the concept excludes subjective elements such as emotional appeal and rhetoric. Dialectic may thus be contrasted with both the eristic, which refers to argument that aims to successfully dispute another's argument, and the didactic method, wherein one side of the conversation teaches the other. Dialectic is alternatively known as minor logic, as opposed to major logic or critique. Within Hegelianism, the word dialectic has the specialised meaning of a contradiction between ideas that serves as the determining factor in their relationship. Dialectical materialism, a theory or set of theories produced mainly by Karl Marx and Friedrich Engels, adapted the Hegelian dialectic into arguments regarding traditional materialism. The dialectics of Hegel and Marx were criticized in the twentieth century by the philosophers Karl Popper and Mario Bunge. Dialectic tends to imply a process of evolution and so does not naturally fit within classical logics, but was given some formalism in the twentieth century. The emphasis on process is particularly marked in Hegelian dialectic, and even more so in Marxist dialectical logic, which tried to account for the evolution of ideas over longer time periods in the real world. There is a variety of meanings of dialectic or dialectics within Western philosophy. In classical philosophy, dialectic is a form of reasoning based upon dialogue of arguments and counter-arguments, advocating propositions and counter-propositions. The outcome of such a dialectic might be the refutation of a relevant proposition, or of a synthesis, or a combination of the opposing assertions, or a qualitative improvement of the dialogue. Moreover, the term dialectic owes much of its prestige to its role in the philosophies of Socrates and Plato, in the Greek Classical period. Aristotle said that it was the pre-Socratic philosopher Zeno of Elea who invented dialectic, of which the dialogues of Plato are the examples of the Socratic dialectical method. According to Kant, however, the ancient Greeks used the word dialectic to signify the logic of false appearance or semblance. To the Ancients, it was nothing but the logic of illusion. It was a sophistic art of giving to one's ignorance, indeed even to one's intentional tricks, the outward appearance of truth, by imitating the thorough, accurate method which logic always requires, and by using its topic as a cloak for every empty assertion. The Socratic dialogues are a particular form of dialectic known as the method of elenchus whereby a series of questions clarifies a more precise statement of a vague belief, logical consequences of that statement are explored, and a contradiction is discovered. The method is largely destructive, in that false belief is exposed and only constructive in that this exposure may lead to further search for truth. The detection of error does not amount to a proof of the antithesis; for example, a contradiction in the consequences of a definition of piety does not provide a correct definition. The principal aim of Socratic activity may be to improve the soul of the interlocutors, by freeing them from unrecognized errors; or indeed, by teaching them the spirit of inquiry. In common cases, Socrates used enthymemes as the foundation of his argument. For example, in the Euthyphro, Socrates asks Euthyphro to provide a definition of piety. Euthyphro replies that the pious is that which is loved by the gods. But, Socrates also has Euthyphro agreeing that the gods are quarrelsome and their quarrels, like human quarrels, concern objects of love or hatred. Therefore, Socrates reasons, at least one thing exists that certain gods love but other gods hate. Again, Euthyphro agrees. Socrates concludes that if Euthyphro's definition of piety is acceptable, then there must exist at least one thing that is both pious and impious—which Euthyphro admits is absurd. Thus, Euthyphro is brought to a realization by this dialectical method that his definition of piety is not sufficiently meaningful. In another example, in Plato's Gorgias, dialectic occurs between Socrates, the Sophist Gorgias, and two men, Polus and Callicles. Because Socrates' ultimate goal was to reach true knowledge, he was even willing to change his own views in order to arrive at the truth. The fundamental goal of dialectic, in this instance, was to establish a precise definition of the subject (in this case, rhetoric) and with the use of argumentation and questioning, make the subject even more precise. In the Gorgias, Socrates reaches the truth by asking a series of questions and in return, receiving short, clear answers.