philosophers' stonen.

Etymology: < the genitive plural of philosopher n. + stone n., after post-classical Latin lapis philosophorum the stone of the philosophers (13th or 14th cent.; compare philosopher n. 1a), from the post-classical Latin uses of classical Latin lapis in this sense (12th or 13th cent.), after the Hellenistic Greek or Byzantine Greek use of ancient Greek λίθος in this sense (4th cent. or earlier) and the post-classical Latin use of classical Latin philosophōrum to identify alchemical apparatus and processes (12th or 13th cent.), after the Hellenistic Greek or Byzantine Greek use of ancient Greek ϕιλόσοϕος in the sense ‘alchemist’ (4th cent. or earlier), in both cases via Arabic intermediary forms; compare Byzantine Greek λίθος τῶν σοϕῶν (7th cent.?); compare also post-classical Latin lapis philosophicus (13th of 14th cent.), lapis philosophalis (15th cent.), and ignis philosophorum philosopher's fire (12th or 13th cent.): see note below. Compare Middle French pierre du philosophe (late 14th cent., rare), Middle French, French †pierre des philosophes (c1400 in Middle French, subsequently 1721 in Trévoux Dict.), pierre philosophale (15th cent. in Middle French, now rare and usually in figurative sense ‘a thing which is extremely difficult to find, or about which nothing is known’), pierre philosophique (a1590), Catalan pedra philosofal (late 15th cent.), Spanish piedra filosofal (1511 or earlier), Italian pietra filosofale (1585), early modern German philosophischer stein (1605), German Stein der Weisen (1582 as Stein der Weysen), †Weisenstein (1689).Many of the texts in which the post-classical Latin and Greek forms occur are hard to date with certainty, but the evidence suggests that the form lapis philosophorum was neither the first name for the philosophers' stone to be used in Latin alchemical texts nor, until the 15th or 16th cent., the most common. It does not appear in three major texts to which early dates can be assigned, all of which are translations from Arabic: the Liber de compositione alchemiae (12th or 13th cent.) refers to the philosophers' stone simply as lapis , although it does use the form ignis philosophorum ‘the philosophers' fire’; the Latin version by Philippus Tripolitanus of the pseudo-Aristotelian Secreta secretorum (early 13th cent.) calls it lapidem..qui non est lapis ‘the stone which is not a stone’, adding that it is also known as ovum philosophorum ‘the philosophers' egg’ (see egg of philosophers n. at philosopher n. Phrases 1, philosophers' egg n. at philosopher n. Compounds 3; both of these Latin phrases are direct translations from the Arabic, and the former goes back ultimately to Hellenistic Greek or Byzantine Greek λίθος ὁ οὐ λίθος (4th cent. a.d. or earlier)); the Turba philosophorum (13th cent.) likewise refers to it as lapis and res..quae lapis est et non lapis. The form lapis philosophorum is found by the late 13th or early 14th cent. in some manuscripts of the pseudo-Geberian summa perfectionis, but appears at first to be less common than lapis noster ‘our stone’ (for which see Dict. of Medieval Latin from British Sources s.v. lapis 15a); it coexists with periphrases such as lapidem magnum quem omnes philosophi quesierunt ‘the great stone which all philosophers have sought’ (Joannes de Rupescissa De confectione veri lapidis philosophorum). The form lapis philosophicus appears in other early manuscripts of the summa perfectionis, and the rarer lapis philosophalis in at least one 15th-cent. source, but by the end of the 16th cent. lapis philosophorum was increasingly the preferred form, appearing in a wide variety of occult texts.