Logic and dialectic

Logic and dialectic were already used as synonyms by the ancients, although logizesthai—to think over, consider, calculate—and dialegesthai—to converse—are two very different things. The name dialectic—dialectic, dialectical inquiry, dialectician—was first used by Plato, according to Diogenes Laertius. In the Phaedrus, Sophist, Republic, book 7, and elsewhere, we find that he understands it as the orderly use of reason and proficiency in its use. Aristotle uses “dialectical matters” in the same sense; but, according to Laurentius Valla, he was the first to use “logic” in this sense. In his writings we find “logical difficulties,” that is, subtleties, “a logical proposition,” and “a logical perplexity.” Accordingly, “dialectic” would be older than “logic.” Cicero and Quintilian use Dialectica and Logica in the same general sense. Cic. in Lucullo: “Dialectic was invented as, so to speak, an arbiter between truth and falsehood.” And: “The Stoics carefully pursued the methods of judgment in that science which they call dialectic.” Cic. Topica, c. 2. Quinct. lib. [XII,2]: “And so this part of dialectic—or, if we prefer to call it so, disputation.” He therefore seems to regard the latter as the Latin equivalent of “dialectic.” So far, following Petri Rami dialectica, Audomari Talaei praelectionibus illustrata. 1569. This use of the words logic and dialectic as synonyms persisted through the Middle Ages and into more recent times, down to the present. In modern times, however, especially in Kant, “dialectic” has often been used in a bad sense, as “the sophistical art of disputation”; hence the preference for the more innocent name “logic.” Yet the two originally mean the same thing, and in recent years they have once again been treated as synonyms.

It is a pity that “dialectic” and “logic” have been used as synonyms from ancient times, leaving me less freedom than I would otherwise wish to distinguish their meanings: to define “logic”—from logizesthai, to think over, calculate, itself from logos, word and reason, which are inseparable—as “the science of the laws of thought, that is, of the procedure of reason”; and “dialectic”—from dialegesthai, to converse, every conversation communicating either facts or opinions, and thus being historical or deliberative—as “the art of disputation,” in the modern sense of that word. Logic would then plainly have an object determinable purely a priori, without empirical admixture: the laws of thought, the procedure followed by reason, by logos, when left to itself and undisturbed—that is, in the solitary thinking of a rational being led astray by nothing. Dialectic, by contrast, would concern the association of two rational beings who consequently think together. As soon as they fail to agree like two clocks keeping the same time, this becomes a dispute, a contest of minds. As pure reason, the two individuals would necessarily agree. Their differences spring from the diversity essential to individuality and are therefore an empirical element. Logic, the science of thought, of the procedure of pure reason, could accordingly be constructed entirely a priori; dialectic, for the most part, only a posteriori: from experience of the disturbances that diversity of individuality brings to pure thought when two rational beings think together, and of the means individuals employ against one another to establish each one's own thinking as pure and objective. For human nature brings it about that when, in thinking together—dialegesthai, the communication of opinions, historical conversations excluded—A learns that B's thoughts on the same subject differ from his own, he does not first revise his own thinking to find the error, but assumes it to lie in the other's. In other words, a human being is by nature bent on being right. What follows from this quality is taught by the discipline I would like to call dialectic, but, to avoid misunderstanding, shall call “eristic dialectic.” It would therefore be the study of the procedures of humanity's natural insistence on being right.

The ancients already treated logic and dialectic as words for the same thing. Yet logizesthai means thinking something over, considering it or calculating, while dialegesthai means talking with someone. These are very different activities. According to Diogenes Laertius, Plato first used the name dialectic: dialectic, the study of dialectic, and a dialectician. In the Phaedrus, Sophist, Republic lib. 7 and elsewhere, he means reasoning according to rules and being skilled at it. Aristotle uses “dialectical matters” with the same meaning. But Laurentius Valla says Aristotle was the first to use “logic” this way. We find in his works “logical difficulties,” meaning subtleties, “a logical proposition,” and “a logical puzzle.” So the name “dialectic” would be older than “logic.” Cicero and Quintilian use Dialectica and Logica with the same broad meaning. Cic. in Lucullo: “Dialectic was invented as a kind of judge between true and false.” And: “The Stoics carefully investigated ways of judging in the science they call dialectic.” Cic. Topica, c. 2. Quinct. lib. [XII,2]: “So this part of dialectic, or debating, if we prefer to call it that.” He seems to take the latter word as the Latin equivalent of dialectic. So far, this follows Petri Rami dialectica, Audomari Talaei praelectionibus illustrata. 1569. People continued using logic and dialectic as synonyms in the Middle Ages and in modern times, right up to today. In more recent times, though, particularly in Kant, “dialectic” has often had a bad meaning: the sophistical art of debating. People have therefore preferred the less objectionable name “logic.” Originally, however, the two mean the same thing. In the last few years people have again treated them as synonyms.

It is unfortunate that “logic” and “dialectic” have been treated as synonyms for so long. It stops me from separating their meanings as freely as I would like. I would define “logic” as “the science of the laws of thinking, or the way reason works.” Its name comes from logizesthai, to think over or calculate, and from logos, word and reason, which cannot be separated. I would define “dialectic” as “the art of debating,” in the modern meaning of that word. It comes from dialegesthai, to converse. A conversation communicates either facts or opinions, so it is either historical or concerned with deliberation. Logic would clearly have a subject we could determine entirely a priori, without mixing in experience. That subject is the laws of thinking: the way reason, logos, proceeds when left alone and undisturbed. It concerns a rational being thinking alone, with nothing to mislead it. Dialectic would instead concern two rational beings thinking together. As soon as they fail to agree like two clocks keeping time together, their thinking becomes a dispute, a mental contest. As pure reason, both people would have to agree. Their disagreements come from the differences that belong to individuality. These are therefore a matter of experience. Logic, the science of thinking and of how pure reason proceeds, could thus be developed entirely a priori. Dialectic could be developed mostly only a posteriori: from experience of how differences between individuals disturb pure thinking when two rational beings think together, and of the methods each uses against the other to get their own thinking accepted as pure and objective. Human nature works like this: when A and B think together and exchange opinions—leaving aside conversations about historical facts—and A finds that B thinks differently about the same subject, A does not first examine their own thinking for a mistake. A assumes the mistake is in B's thinking. In other words, people are naturally determined to be right. The discipline that teaches the procedures arising from this trait is what I would like to call dialectic. To prevent misunderstanding, I will call it “eristic dialectic.” It would study the methods people use in their natural determination to be right.