# Supplement to the Fourth, Fifth, and Sixth Editions of the Encyclopædia Britannica/Agnesi (Maria Gaetana)

​AGNESI (Maria Gaetana), an Italian lady, who may be justly pronounced one of the greatest wonders and ornaments of her sex, was born at Milan on the 16th of May 1718. Our materials for an account of this celebrated female are by no means so complete, nor in some interesting particulars so distinct, as we could have wished. Not having been ​able to procure her Eloge by Frisi, we have been obliged to content ourselves with some shorter notices; the most detailed of which is that contained in Mazzuchelli’s History of the Writers of Italy, a work published during the earlier, but more brilliant period of her life. The accounts which this writer and some others have given of the intellectual capacities and endowments which she displayed in early youth, call to mind the wonders which have been related of Picus of Mirandula, and the Admirable Crichton. Nor does there seem any reason to doubt their authenticity. At nine years of age, she not only spoke the Latin language with precision, but even composed and delivered an oration in that language, intended to prove that the cultivation of letters is not incompatible with the female character. This singular piece was published at Milan the same year in which it was spoken, with the following title: Oratio qua ostenditur artium liberalium studia a fæmineo sexu neutiquam abhorrere, habita a Maria de Agnesiis rhetoricæ operam dante anno ætatis suæ nono nondum exacto, die 18 Augusti 1727.
At eleven years of age, she spoke Greek with all the fluency of her native tongue. When yet very young, she had also acquired some of the languages of the East; and, in a word, her acquisitions as a linguist were such, as to procure for her the appellation of a Walking Polyglott. But her aptitude for acquiring languages, however great, was by no means the only, or the most striking feature of her intellectual character. We have seen how early she essayed the discussion of a general question affecting the mental capacities of hey sex, and the vigour and acuteness displayed in this aspiring essay were, ere long, exerted with ardour and success in scientific inquiries. Having gone through the elementary branches of mathematics, she proceeded with alacrity to the study of natural philosophy; and she seems also to have carried her researches into the obscurer regions of metaphysical speculation.
About the time when she reached her fifteenth year, her father formed a select assembly of the learned of Milan, and at these meetings, which were held in his house, at stated times, for several years, Agnesi maintained a succession of Theses on various points of speculation and philosophy. The ability which she displayed on these occasions seems to have been altogether surprising; and the effect was not the less, that her person was agreeable, and her whole deportment gentle and prepossessing. We are indebted to the learned President De Brosse for the following account of one of these conferences, at which he assisted during his travels in Italy, through the introduction of Count Belloni. “I had conceived,” says he, “when I went to this conversatione, that it was only to talk with this young lady in the usual way, though on learned subjects; but to my surprise, Belloni addressed her in a fine Latin harangue, with all the formality of an academic oration. She replied in the same language, with promptness and ability; and they proceeded, still in Latin, to discuss the origin of fountains, and the causes of the ebbings and flowings observed in some of them. She spoke like an angel on this subject, and I never heard it treated so much to my satisfaction. We then discoursed with her concerning the manner in which the soul receives impressions from outward objects, and their conveyance to the general sensorium, the brain; and afterwards upon the propagation of light, and the prismatic colours. The conversation afterwards became general, every one speaking to her in the language of his own country, and she answering in the same.” (Lettres sur l’Italie, Tom. I. p. 243.) But Agnesi seems to have taken but little delight in the glory which she acquired as a philosophical disputant. Her temper was retired and devout, and she appears to have acted this part more to gratify her father than herself. About her twentieth year, she accordingly withdrew from these assemblies, and for a long period devoted the greater part of her time to mathematical studies. The Theses which she had maintained with so much applause were published in a quarto volume, under the following title: Propositiones Philosophicæ quas crebris disputationibus domi habitis coram clarissimis viris explicabit extempore et ab objectis vindicabat Maria Gaetana de Agnesiis Mediolanensis. Med. 1738.
The first fruit of her mathematical studies was a Commentary on the Conic Sections of the Marquis de l’Hospital; but this piece she would never consent to publish, though Mazzuchelli says that it was greatly praised by many who had perused the manuscript. In the course of a few years, however, she gave to the world a mathematical work, which must ever secure her a high rank among the most distinguished cultivators of abstract science. This work, entitled Instituzioni Analitiche ad uso della Gioventu Italiana, was published at Milan in 1748, in two volumes quarto. The first volume treats of the analysis of finite quantities; the second, of the analysis of infinitesimals. These two volumes contain a full and satisfactory view of this branch of mathematical science in the state at which it had then arrived; and though improvements have since that time been introduced, the treatise of Agnesi, according to a very competent authority, may still be regarded as perhaps the best introduction that is to be found to the works of Euler, and the other mathematicians of the Continent. (Edinb. Review, Vol. III. p. 408.)—An English translation of this work was long ago executed by the late Professor Colson of Cambridge, but the manuscript lay buried in obscurity for many years, and was only published in 1801, through the care and at the expence of Baron Maseres.
Besides other literary honours which followed the publication of the Analytical Institutions, Agnesi was, in 1750, appointed Professor of Mathematics and Natural Philosophy in the university of Bologna. The appointment of a young female, of thirty-two years of age, to such a charge, must appear to many ​as not a little singular; but the truth is, that female professors were by no means uncommon in Italy; and La Lande mentions several as having been eminent in the same university, one of whom was Professor of anatomy. (Voyage en Italie, Tom. II.) Our scanty information does not enable us to state whether Agnesi ever entered upon the active duties of the mathematical chair. Though her life was long, we can add but little in regard to her after-history. She died, according to the meagre notice contained in the Biographie Universelle, in the year 1799. Her mistaken notions of religious duty rendered the greater part of her existence but a blank to the world. She had early expressed a wish to retire into a convent, and seems to have carried this design into effect not long after the period when her great work procured for her the honours to which we have just alluded. We afterwards hear of her only as a devoted sister of the austere order of Blue Nuns, repelling the approaches of those of the learned who still desired to converse with her, and thus exhibiting another melancholy instance of the inconsistencies of our nature, and the darkening power of superstition over the brightest minds. But she lived long enough for the world to vindicate the intellectual capacities of her sex,—to show that the female mind is not only fitted for the lighter exercises of literature, but capable also of fathoming the depths, and unravelling the intricacies of abstract science. If there are any, therefore, whose speculations may have led them to more depreciating conclusions, let them, te use the words of a profound and eloquent writer already quoted in this article, “peruse the long series of demonstrations which the author of the Analytical Institutions has contrived with so much skill, and explained with such elegance and perspicuity; if they are able to do so, they will probably retract their former opinions; if unable, they will not of course see the reasons for admiring her genius that others do; but they may at least learn to think modestly of their own.” (Edinb. Rev. Vol, III. p. 410.)