The secrecy of ancient oriental sciences has often been assumed without any attempt to investigate the foundation for such a hypothesis. There exist indeed examples of “cryptographic” writing both in Egypt and Mesopotamia. The Cenotaph of Seti I, for instance, contains cryptographic passages in the mythological inscriptions which are written around the sky goddess. Some of the passages use rare readings of hieroglyphs, some are simply incorrectly arranged lines of the original from which the artist copied. In a related text concerning a sun dial the words are written backwards, as if reflected by a mirror, but this causes no real difficulty in reading the text. On the whole, however, all texts with mathematical and astronomical context show not the slightest intention of concealing their meaning from the reader. I think one can only agree with T. E. Peet, the editor of the mathematical Papyrus Rhind, that we have no reason for assuming the existence of any secret science in Egypt.
The same holds for Babylonia. The Old Babylonian mathematical texts are as plainly written as possible. From the latest period there exist a few texts which give lists of numbers and signs obviously for coding and decoding purposes. A few words and proper names are written in such a code in the colophons of two ephemerides. The ephemerides themselves as well as the procedure texts show no trace of an attempt to hide their contents. If many details remain unintelligible to us, it is our ignorance and missing texts which cause the difficulties, not an intentionally cryptic writing. I think the remark found occasionally in colophons of Uruk texts that the text should only be shown to “the informed” is not to be taken too seriously. It hardly indicates much more than professional pride and feeling of importance of members of the scribal guild.
Cryptographic devices occur also in Greek manuscripts of the Byzantine period, based, e. g., on a simple substitution of letters and their numerical values in inverse order; cf. e. g., V. Gardthausen, Griechische Palaeographie II (2nd ed., Leipzig 1913) p. 300 ff. Magical texts are, of course, full of secret combinations of letters; astrological texts, however, are practically free of such secrecy.
Otto Neugebauer, The Exact Sciences in Antiquity. Second edition. (Brown University Press, 1957). Page 144.