GALILEI, Galileo (1564-1642). Il saggiatore nel quale con bilancia esquisita e giusta si ponderano le cose contenute nella libra astronomica e filosofica di Lotario Sarsi. Rome: Giacomo Mascardi, 1623.
4o (213 x 152 mm). Engraved title by F. Villamena, 18 engraved diagrams in text, typographic headpiece ornament, woodcut initials and tail-pieces. 16 lines of errata on Ff6v (last text page). (Lacking engraved portrait, supplied in facsimile, occasional light browning, light dampstaining in quire C, small wormtrack affecting upper portion of text of a dozen leaves, minor marginal repair to Aa2.) 19th- or 20th-century vellum over pasteboard, earlier calf lettering-piece preserved.
Provenance: Giacomo d'Ambosa, doctor of medicine and philosopher (1680 inscription on title).
FIRST EDITION, FIRST ISSUE, on thicker paper with the shorter errata. Galileo's masterful polemic on the new science was written in response to Orazio Grassi, mathematician at the Jesuit Roman College, who in 1619 had published, under the pseudonym Lotario Sarsi, an attack on Galileo after the latter had criticized his views on comets. Unable to defend the Copernican doctrine, declared heretical in 1616, Galileo avoided all discussion of the world's movement in his response, addressed to a young admirer named Virginio Cesarini, concentrating instead on a general discussion of the proper scientific approach to the investigation of celestial phenomena. The crux of his argument was that no theory of comets could be advanced unless it could be proven that they were concrete moving objects rather than mere optical effects of solar light, a proof that he considered impossible. In advancing this thesis he set forth some fundamental axioms of the modern scientific method: he "distinguished physical properties of objects from their sensory effects, repudiated authority in any matter that was subject to direct investigation, and remarked that the book of nature, being written in mathematical characters, could be deciphered only by those who knew mathematics" (DSB).
Il Saggiatore was dedicated at the last minute to the new Pope Urban VIII, Maffeo Barberini, Galileo's friend and a patron of science and the arts. Galileo was in Florence during the printing and could not supervise the corrections, so the first issue contains only 16 errata; Galileo had an additional errata leaf printed for the second issue, which was revised to a total of 137 errata for the third and final issue. This copy includes the often lacking four preliminary leaves (signature a4) containing commendatory verses by Johannes Faber and Francesco Stelluti. The engraving on Ee1r is the earliest published illustration of the ring of Saturn, the planet Mars in inferior and superior conjunction, and the phases of Venus. According to Mario Biagioli (Galileo courtier, p. 297), the edition had a press-run of fewer than 400 copies.
Carli and Favaro 95; Cinti 73; Riccardi I, 511; Norman 857.