Sophism

SOPHISM. - In primitive usage σύφισμα (from σοφία, wisdom) is every contrivance or invention of thought (inventum, scitum). After dialectic, through sophistry (v. SOPHISTS), was made to serve negative ends by verbalistic expedients (cf. the examples reported by Aristotle in the De sophisticis elenchis, ch. 4 ff.), the term s. also took on a pejorative sense and was used to indicate an illogical (or false) argument that is apparently correct: «when it seems to prove, it will be a sophism, not a demonstration» (ἐν δὲ φαίνεται, σύφισμα ἔσται, οὐκ ἀπόδειξις: Top., VIII, 11, 162 a 14-15; cf. De soph. el., 1, 165 a 21; and Sextus Emp., Pyrrh. hypoth., II, 22, 229 ff.: «sophisms wound the truth with an appearance of verisimilitude»).

The further meaning taken on by the term, as an intentionally captious argument — whereby s. is sometimes distinguished from simple paralogism or illogical argument — is likewise of sophistic derivation: such a sense is not found explicitly in Aristotle, who identifies s. and paralogism (De soph. el., 1, 164 a 21), but it is nevertheless contained in the qualification of s. as a «contentious argument» (σύφισμα δὲ συλλογισμὸς ἐριστικὸς: Top., VIII, 11, 162 a 16-17; cf. 12, 162 b 3-5; cf. Reth., 1, 1355 b 17: «the sophist is such by deliberate choice», κατὰ τὴν προαίρεσιν) and in the assertion that the sophist aims to draw profit from an apparent science (De soph. el., 1, 165 a 22). The aforementioned meaning is instead expressed by the Latin term «fallacia» (from fallere, to deceive), used in the Middle Ages as a synonym of s. (but already Seneca, after Cicero, rendered s. with «cavillatio»; cf. Ep., 111, and Cic., Acad., IV, 24, 75: «sophismata appellantur fallaces conclusiunculae»; cf. also St. Augustine, De doctr. christ., II, ch. 34, n. 48). There is finally a third meaning — debatable moreover — indicated by Lalande (Vocab. techn. et crit. de la philos., 5th ed., Paris 1947, pp. 989-90), according to which s. is an argument that from true premises, or premises accepted as such, leads to impossible and paradoxical conclusions and yet does not appear refutable because it is logically correct: such, for example, according to some, are the arguments of Zeno or the Kantian antinomies. The existence of such sophisms would show, according to Lalande, that the laws of logic «n'ont pas un champ d'application illimité» (loc. cit.).

A classification of the various forms of s. and at the same time a detailed exposition of the methods for countering them is given by Aristotle in the De soph. el., ch. 4 ff. Aristotle distinguishes the forms of s. deriving from expression or language («secundum dictionem»): equivocation in terms; ambiguity of the sentence; variation in accent; passage from the divided sense of a proposition to the compound sense and vice versa; similarity of expression (cf. ch. 4, 165 b 24 ff.); and the forms extraneous to language («extra dictionem»): attribution to the subject of what belongs only to one of its determinations, fallacia accidentis; acceptance in an absolute sense of what is true only in a determinate sense, dictum simpliciter et dictum secundum quid; ignorance or confusion of the argument, ignorantia elenchi; defect of inference, fallacia consequentis; assumption as a premise of what must be demonstrated, petitio principii; confusion of what is not a cause with the cause, non causa pro causa; complex question that demands contrary answers, proposed as a single question: sophisma plurium interrogationum ad modum unius (cf. ch. 5, 166 b 28 ff.). The Aristotelian classification was drawn from the practice of ancient sophistry. Among the further forms of s. not listed in Aristotle's logic, and from which the methodology of modern science has not always been exempt, the following should be remembered: generalization founded on an insufficient induction (sophisma inductionis) or on simple analogy (sophisma analogiae), and deductions from a hypothesis presented as certain truths (sophisma hypothesis).

Ugo Viglino