A maxim from 18th century textual criticism which states that the shorter reading tends to be the better (older) one, as scribes have a tendency to incorporate explanatory secondary glosses into the text. It seems to be first used by Bengel (1734, p. 778: plerumque, si non semper, genuina est lectio brevior, verbosior interpolata). But already Le Clerc realised that this rule of thumb is much less valuable than lectio difficilior, lectio potior (cf. Timpanaro 1963, 39), as there are many cases in which text may get lost in transmission, e.g. by eye-skip (see error).
Reference
– Bengelius, Johannes Albrecht, ed. 1734. Ἡ Καινὴ Διαθήκη. Novum Testamentum Graece. Stutgardiae: apud I. B. Metzlerum.
– Lorimer, William L. 1934. “Lectio Difficilior.” The Classical Review 48 (5): 171–173.
– Timpanaro, Sebastiano. 1963. La genesi del metodo del Lachmann. Firenze: Le Monnier.
– ———. 1981. La genesi del metodo del Lachmann. 2nd ed. Padova: Liviana.
– ———. 2005. The Genesis of Lachmann’s Method. Translated by Glenn W. Most. Chicago: University of Chicago Press. – Translated from Timpanaro 1981.