吉安巴蒂斯塔·德拉·波尔塔Giambattista della Porta

吉安巴蒂斯塔·德拉·波尔塔的父亲是Nardo Antonio Della 波尔塔，一个相当富有且重要的人，拥有土地和船只。波尔塔的母亲是Adriano Guglielmo Spadafora的姐妹，后者是一位学者，在那不勒斯档案馆担任conservator。从1541年起，Nardo Antonio在皇帝Charles V麾下担任Scrivano di Mandamento，意即他是皇帝负责向代牧区提出民事上诉的秘书。Charles V当时是神圣罗马帝国皇帝和西班牙国王，他的帝国横跨欧洲，远至尼德兰、奥地利和那不勒斯王国。Nardo Antonio在那不勒斯城内及周边拥有三处房产：一处在那不勒斯城内，一处位于城市西北山丘中Due Porte的别墅，还有一处位于Sorrento东北那不勒斯湾畔Vico Equense的宏伟宅邸。尽管没有确凿证据，但由于波尔塔在Vico Equense的教堂中行使的权利只有出生在该镇的人才能享有，几乎可以肯定他出生在那里的家族宅邸Villa delle Pradelle。他是父母四个儿子中的第三个，但一个哥哥在童年夭折，使波尔塔有一个哥哥Gian Vincenzo和一个弟弟Gian Ferrante。

波尔塔 接受了私人教师的良好教育，但他教育中的一个重要部分来自他的父亲，因为他的父亲是一位知识分子，其家成为哲学家、数学家、诗人和音乐家的聚会场所。通常这群博学之士在拿坡里的 Nardo Antonio 家中聚会，但有时在炎热的天气里，他们选择在维科埃昆塞的 Villa delle Pradelle 聚会。关于科学话题的讨论经常进行，Nardo Antonio 的三个儿子都参与其中。鉴于 波尔塔 的父亲热衷于学习，自然会假设他监督儿子的教育，但就 波尔塔 的情况而言，这似乎并非如此，因为制定主题计划的是 Adriano Guglielmo Spadafora，他母亲的兄弟。回到私人教师，他们是拿坡里的顶尖专家，包括古典学者 Domenico Pizzimenti，以及哲学家和医生 Donato Antonio Altomare 和 Giovanni Antonio Pisano。数学和医学是他教育中最强调的主题，据认为他很可能参加了当时这些主题的顶尖专家 吉罗拉莫·卡尔达诺 的讲座。

波尔塔今天以剧作家闻名，但我们特别感兴趣的是他对科学的重要贡献，我们将在下文加以考察。他的剧作难以确定年代，但一般认为他年轻时就开始写剧本 [4]：-

……可以稳妥地推测，他少年时代便初次尝试写剧本，而他发表的一些喜剧是对最初为家人和朋友中的业余演员所写脚本的修订；他同时代人后来几次提到波尔塔少年早慧的文学才能，也支持这一结论。

他一定是在古典学者Pizzimenti授课期间开始写剧本的。大约同一时期，可能是在十五岁左右，波尔塔正在用磁体和化学物质做科学实验。在详细讨论他的贡献之前，我们应当把当时的科学放在恰当的背景中来看。我们通过引用Shea [20]来做这件事：-

……他所实践的科学已不再是我们所知道的科学。十六世纪第一个十年之后，当时波尔塔仍然活跃，科学、尤其是科学的形象迅速演变。在波尔塔的时代，天文学家仍是占星家，物理学家则是魔术师；而到十七世纪末，占星术已与天文学分离，魔法要么受到非难，要么沿着可辨认的理性路线被重新解释。波尔塔以文艺复兴学者的精神涉猎魔法，而十七世纪初唯一能对他产生真正同情的科学人物是约翰内斯·开普勒，他以如此矛盾的方式把对自然的旧观点和新观点结合在一起。

1558年，当波尔塔二十三岁时，他出版了四卷本的Magiae naturalis, sive de miraculis rerum naturalium。在这本书中，他考察了自然界，声称自然哲学家可以通过理论和实践实验来操纵它。这部著作讨论了许多主题，包括恶魔学、磁学和暗箱。尽管用拉丁文写成，这部著作后来被翻译成法语、意大利语和德语，因此成为广泛阅读的畅销书。Della 波尔塔，对他来说名声很重要，非常自豪于被翻译成不同语言的事实。大约在1560年，波尔塔成立了一个学会，Accademia dei Segreti（秘密学院），致力于讨论和研究自然；定期会议在他的家中举行，即位于维科埃昆塞的Villa delle Pradelle。要获得进入该学院的资格，一个人必须展示他们发现了关于世界的一个事实，而这个事实对其他人来说是未知的。我们知道一些关于“发现”的事情，因为波尔塔在1589年出版的一部大大扩展的二十卷版Magiae naturalis中报告了一些。Accademia dei Segreti在1578年左右被宗教裁判所关闭，此前他们审查了波尔塔。关于他被宗教裁判所审查的情况，或许并不令人惊讶地，存在相互矛盾的信息。一份报告称，他以他的学识给他们留下了深刻印象，并使他们相信他所做的一切都是“自然的”。这看起来像是波尔塔自己的版本，因为他总是准备歪曲事实以使自己看起来很好；他在其他几个问题上也这样做了，比如他的年龄。更可信的报告说，他因首先不得不为自己辩护，然后撤回自己的观点而遭受了巨大的“灵魂痛苦”，可能还遭受了短暂的监禁。当然，在被传唤到宗教裁判所之后，他加入了耶稣会，每周花一天时间从事慈善工作和宗教职责。尽管做出了这些在宗教上正确的尝试，他一生中仍不得不与宗教裁判所作斗争，他的一些文本从未被批准出版。

在Accademia dei Segreti运作的那些年里，Della 波尔塔 在意大利、法国和西班牙广泛旅行，但总是回到那不勒斯附近的庄园，在那里他可以平静地研究。他在1589年版Magiae naturalis的序言中解释说，每当他访问法国或西班牙时，他总是会见领先的学者，参观图书馆，购买尽可能多的书籍，并总是寻求学习关于物理世界的新“秘密”。他从来不需要谋生，因为家族的财富似乎足以让他致力于研究。然而，运营学院以及实验所涉及的相当大成本，占用了家族财富的很大一部分，有迹象表明一些成本削减变得必要。同样在这些年里，他出版了De furtivis literarum（1563年），这是一部关于密码学的著作，其中他收集了大量不同的系统。这部作品，他在访问西班牙期间亲自呈献给西班牙国王菲利普二世，大大增加了波尔塔本已很高的声望。1566年，他出版了Arte del ricordare，在这部作品中他解释了如何使用助记设备来提高记忆力。我们从这部作品中了解到，波尔塔的记忆更多是由于他的分类和组织能力，而不是天赋。

在某个阶段，波尔塔结婚了，但他妻子的名字未知，似乎她年轻时就去世了。他们有一个女儿Cinzia，她嫁给了Alfonso di Costanzo。如果波尔塔的婚姻产生了任何其他孩子，他们在父亲之前去世，因为Cinzia是他在遗嘱中提到的唯一孩子。

1579年11月，波尔塔受邀加入红衣主教Luigi d'Este的服务。由于需要一位赞助人，他两个月后搬到罗马，住在Palazzo d'Este。他由红衣主教资助进行科学工作，但引起了问题，因为他[4]：-

……坚持晚饭后立即上床睡觉，起得很早，在早餐前吵闹地学习，并要求在他工作或睡觉时保持完全安静。

波尔塔向红衣主教报告了他的实验，还寄给他两部戏剧，一部喜剧和一部悲喜剧；其中第一部被搬上舞台。事实上，他是为红衣主教工作的众多剧作家之一，如Torquato Tasso，文艺复兴晚期最伟大的意大利诗人。在经历了一段疾病之后（波尔塔经常发烧），他于1580年12月在威尼斯加入了红衣主教。在那里，他研究抛物面镜和透镜，发现威尼斯在玻璃方面的专业知识对他非常有帮助。他还在费拉拉的Duke Alfonso II d'Este宫廷度过了一段时间，但在1581年4月他回到那不勒斯，尽管继续为红衣主教工作。如同他早期的学院一样，他的家成为该地区学者的聚会场所。像当时的许多科学家一样，他忙于试图将贱金属变成黄金，他相信自己已经找到了秘密[4]：-

他的希望被争吵、家庭麻烦和源源不断的访客所延迟，那不勒斯人和外国人涌向波尔塔家中的非正式学院，使他无法入睡，逼得他绝望，最糟糕的是，阻止他测试他的新秘密。

听到这个消息后，红衣主教命令波尔塔立即来罗马向他报告，但在进行进一步实验后，波尔塔发现他的方法不成功。然而，他确实在1586年10月访问了罗马的红衣主教。这是他们最后一次见面，因为红衣主教于1587年去世。

波尔塔出版了Pomarium（1583）关于种植果树和Olivetum（1584）也关于照顾树木。这两部作品都是Villae（1592）的一部分，一部农业百科全书。在De humana physiognomonia（1583）中，他将注意力转向动物和人类，调查行为如何与外貌相关联。这个话题被罗马天主教会相当怀疑，当时它正在将许多作品列入禁书目录。经过三年的漫长等待，这本书被官方审查员批准。在书中，他描述了自己的外貌，但像波尔塔通常一样，这是一个理想化的版本，与他人的描述不一致。他有一张瘦脸，深陷的明亮眼睛，一个长而不规则形状的鼻子，和一个独特的高额头。

他写过的其他主题包括De distillatione（1609）中的化学、力学，以及Elementa curvilineorum（1601）中的squaring the circle 。这部作品由Hofmann在[13]中详细描述，使用欧几里得方法研究由圆弧和直线界定的区域。主要成就是证明任何直角三角形的两个月牙形面积之和等于三角形的面积，但波尔塔然后错误地推断每个单独的月牙形可以化为等面积的正方形。在他的其他成就中，包括在De' spiritali（1606）中描述蒸汽机，以及第一个认识到光线的加热效应。

Accademia dei Lincei于1603年由Federico Cesi在罗马创立，其灵感来自波尔塔的Magiae naturalis。该科学院的徽章——目光锐利的猞猁，取自波尔塔著作的扉页。Magiae naturalis的序言中有这样的话：-

……以猞猁般的眼睛，审视那些显现自身的事物，以便在观察之后，能热心地加以利用。

波尔塔大力鼓励Cesi建立他的科学院，1610年，Cesi来到那不勒斯，建立Accademia dei Lincei的一个分支。1610年7月6日，波尔塔成为该分支的主席。在他生命的最后几年，他饱受健康不佳之苦，特别是他一生中经常发作的发烧，还有肾结石，病情逐渐恶化，直到他卧床不起。

现在让我们再稍微看看1584年版二十卷的Magiae naturalis。第17卷讨论光学，第6章清楚地描述了暗箱。他是第一个提出在暗箱上添加凸透镜的人。在第10章中，波尔塔解释了凹透镜和凸透镜的用途。他写道：-

凹透镜能使人最清楚地看到远处的东西；而凸透镜则能看清近处的东西；因此你可以根据视力的需要来使用它们。用凹透镜，你会非常清楚地看到远处的小东西；用凸透镜，较近的东西看起来更大，但更模糊；如果你知道如何把它们组合在一起，你就会看到远处的东西和近处的东西，既更大又清楚。我曾帮助过一些朋友，他们看远处的东西很弱；看近处的东西又很模糊，使他们能清楚地看到一切。

读了这段话之后，人们很容易把望远镜和显微镜的发明归功于波尔塔。然而，这段话的背景是矫正视力缺陷，所以，尽管人们仍然必须理解他光学工作的重要性，却不能把望远镜和显微镜的功劳归给他。我们只能试图理解他所说的把凹透镜和凸透镜组合在一起是什么意思；也许那就是我们今天认为是伽利略望远镜基本特性的那种安排，或者也许波尔塔描述的是双焦点眼镜。波尔塔的一封未注明日期的信使情况有些混乱，这封信是在伽利略描述了他的望远镜之后写的，他在信中声称自己是第一个发明望远镜的人。当然，他在De refractione, optices parte（1593年）中研究过折射，尽管在伽利略之前他似乎没有建造过望远镜。

Magiae naturalis第7卷讨论磁学。1600年，William Gilbert发表了他著名的De magnete，许多人声称这是第一部关于实验科学的现代著作。然而，波尔塔声称Gilbert：-

……把我《自然魔法》的整个第七卷拿去，分成许多卷，做了一些改动；……他凭自己添加的材料是虚假的、乖戾的、忧郁的；到最后他得出地球在运动的疯狂想法。

我们在上文评论过，波尔塔作为剧作家很有名。他写了三部悲剧、二十九部喜剧和一部悲喜剧；只有十四部喜剧、两部悲剧和那部悲喜剧留存下来。他最著名的两部剧作是La sorella（《姐妹》）和Gli duoifratelli rivali（《两个敌对的兄弟》）。其中第一部是一部[18]

……喜剧，旨在通过严格避免反宗教改革之前意大利喜剧剧场中大量存在的无政府状态和享乐主义来改善公共道德。

Louise Clubb关于Gli duoifratelli rivali写道（见[11]）：-

波尔塔似乎在测试“严肃喜剧”的界限，在不打破统一性和得体规则的情况下加以延伸……通过欺骗、伪装和淫秽走向幸福婚姻，但也包含死亡、耻辱、弑亲和政府不公的威胁，《敌对的兄弟》仍然是喜剧，但只是勉强算得上。

最后，让我们引用波尔塔在Fratelli rivali序言中的原话：-

这些著作更多地是由各国学者的普遍赞誉来评判的；因为它们在世界各地印刷，并被翻译成拉丁语、法语、西班牙语和各种其他语言；它们越是被听到和阅读，就越令人愉悦，并被重印。

Giambattista della Porta's father was Nardo Antonio Della Porta, a man of considerable wealth and importance, owning both land and ships. Giambattista's mother was a sister of Adriano Guglielmo Spadafora, a man of learning who worked as a conservator in the archives in Naples. From 1541 Nardo Antonio was in the service of Emperor Charles V as Scrivano di Mandamento, meaning he was the secretary to the Emperor responsible for civil appeals to the vicariate. Charles V was Holy Roman emperor and king of Spain at this time and his empire extended across Europe to the Netherlands, Austria and the Kingdom of Naples. Nardo Antonio owned three houses in and around Naples, one in the city itself, a villa in Due Porte in the hills northwest of the city, and a magnificent mansion at Vico Equense on the Gulf of Naples northeast of Sorrento. Although no definite proof exists, since Giambattista exercised rights in the church at Vico Equense which were only for those born in the town, it is almost certain that he was born in the family mansion there, the Villa delle Pradelle. He was the third of his parents' four sons, but one older brother died in childhood leaving Giambattista with an older brother Gian Vincenzo and a younger brother Gian Ferrante.

Giambattista was well educated by private tutors but an important part of his education came about since his father was an intellectual whose home became a meeting place for philosophers, mathematicians, poets, and musicians. Usually this group of learned men met in Nardo Antonio's home in Naples but sometimes in hot weather they chose to meet in the Villa delle Pradelle in Vico Equense. Discussions on scientific topics frequently took place and all three of Nardo Antonio's sons took part. Given that Giambattista's father was keen on learning, it would be natural to assume that he supervised his sons' education but certainly in the case of Giambattista this appears not to be so for it was Adriano Guglielmo Spadafora, his mother's brother, who drew up the programme of topics. Returning to the private tutors, these were the leading experts from Naples, including Domenico Pizzimenti, a classicist, and Donato Antonio Altomare and Giovanni Antonio Pisano, who were philosophers and medical doctors. Mathematics and medicine were the topics most emphasised in his education and it is thought likely that he attended lectures given by the leading expert on these topics at the time, Girolamo Cardano.

Della Porta is known today as a playwright, but we are particularly interested in his important contributions to science that we shall examine below. His plays are not easy to date but it is thought that began writing plays when young [4]:-

... it is safe to suppose that he first tried his hand at playwriting in boyhood, and that some of his published comedies were revisions of scripts he originally produced for the amateur players among his family and friends, a conclusion supported by several of his contemporaries' later references to Della Porta's literary precocity.

He must have begun writing plays during lessons given by the classicist Pizzimenti. Around the same time, probably when aged about fifteen, della Porta was conducting science experiments with magnets and chemicals. Before going into any detail about his contributions we should put the science of the day into perspective. We do this by quoting from Shea [20]:-

... science as he practised it is no longer science as we know it. After the first decade of the sixteenth century, when Della Porta was still active, science and especially the image of science evolved rapidly. Whereas in Della Porta's day, the astronomer was still an astrologer and the physicist a magician, by the end of the seventeenth century astrology had been severed from astronomy, and magic was either frowned upon or reinterpreted along recognizably rational lines. Della Porta dabbled in magic in the spirit of a Renaissance scholar, and the only scientific figure of the early seventeenth century that could feel any genuine sympathy for him was Kepler, who combined in such a paradoxical fashion the old and the new outlooks on nature.

In 1558, when della Porta was twenty-three years old, he published the four volume Magiae naturalis, sive de miraculis rerum naturalium. In this book he examined the natural world claiming it can be manipulated by the natural philosopher through theoretical and practical experiment. The work discussed many subjects including demonology, magnetism and the camera obscura. Although written in Latin, the work was later translated into French, Italian and German and so became a popular read widely book. Della Porta, for whom fame was important, was very proud of the fact that translations were made into different languages. Around 1560, della Porta formed a society, the Accademia dei Segreti (the Academy of Secrets), dedicated to discussing and studying nature; regular meetings were held at his home, the Villa delle Pradelle in Vico Equense. To gain admittance to the Academy, a person had to show that they had discovered a fact about the world which was unknown to everyone else. We know something of the "discoveries" for della Porta reported some in a greatly expanded twenty-volume version of Magiae naturalis published in 1589. The Accademia dei Segreti was closed down by the Inquisition around 1578 after they examined della Porta. There is, perhaps not surprisingly, conflicting information about his examination by the Inquisition. One report states that he impressed them with his learning and convinced them that everything he did was "natural". This looks like della Porta's own version for he was always prepared to bend the truth to make himself look good; he did over several other issues, such as his age. The more believable report says that he suffered great "anguish of soul" at having first to defend, and then recant his views, probably suffering a short period of imprisonment. Certainly he joined the Jesuit Order after his summons before the Inquisition and spent one day each week on charity work and religious duties. Despite these attempts to be religiously correct, he had to battle against the Inquisition throughout his life and some of his texts were never approved for publication.

During the years that the Accademia dei Segreti was operating, Della Porta travelled widely in Italy, France and Spain always returning to his estate near Naples where he was able to study in peace. He explains in the preface to the 1589 edition of Magiae naturalis that whenever he visited France or Spain he always met with leading academics, visited libraries, purchased as many books as he could afford, and was always looking to learn new "secrets" about the physical world. He never needed to earn a living as the wealth of the family seems to have been sufficient to allow him to devote himself to study. However, running the Academy with the considerable costs involved in the experiments, took a sizable part of the family's wealth and there are indications that some cost cutting became necessary. Also during these years he published De furtivis literarum (1563), a work on cryptography in which he collected a large number of different systems. This work, which he presented personally to king Philip II of Spain during a visit to Spain, added greatly to della Porta's already high prestige. In 1566 he published Arte del ricordare, a work in which he explained how to use mnemonic devices to improve memory. We learn from this work that della Porta's memory was more due to his ability to categorize and organize than a natural talent.

At some stage della Porta married but the name of his wife is unknown and it seems likely that she died young. They had a daughter, Cinzia, who married Alfonso di Costanzo. If della Porta's marriage produced any further children, they died before their father as Cinzia is his only child mentioned in his will.

In November 1579 della Porta was invited to join the service of Luigi, cardinal d'Este. In need of a patron, he moved to Rome two months later and lived at the Palazzo d'Este. He carried out his scientific work financed by the cardinal but caused problems since he [4]:-

... insisted on going to bed immediately after dinner, rose very early and noisily to study before breakfast, and demanded that total silence be maintained whenever he was working or sleeping.

Della Porta reported to the cardinal on his experiments and also sent him two of his plays, a comedy and tragi-comedy; the first of these was staged. In fact he was one of a number of dramatists who worked for the Cardinal, like Torquato Tasso, the greatest Italian poet of the late Renaissance. After a period of illness (della Porta frequently suffered fevers) he joined the cardinal in Venice in December 1580. There he worked on parabolic mirrors and lenses, finding that the Venetian expertise with glass was very helpful to him. He also spent time at the court of Duke Alfonso II d'Este at Ferrara but in April 1581 he returned to Naples although continuing to work for the Cardinal. As with his Academy in earlier times, his home became the meeting place for the learned men in the area. Like many scientists at this time he occupied himself with attempts to turn base metal into gold and he believed he had found the secret [4]:-

His hopes were delayed by quarrels, domestic troubles, and a steady stream of visitors, Neapolitans and foreigners, who flocked to the informal academy in Della Porta's house, kept him from sleeping, drove him to desperation, and worst of all, prevented him from testing his new secret.

On hearing the news the cardinal ordered della Porta to come immediately to Rome to report to him but after carrying out further experiments, della Porta found that his method was unsuccessful. He did, however, visit the cardinal in Rome in October 1586. It was the last time they met for the cardinal died in 1587.

Della Porta published Pomarium (1583) on growing fruit trees and Olivetum (1584) also on taking care of trees. Both works formed part of Villae (1592), an agricultural encyclopaedia. In De humana physiognomonia (1583) he turned his attention to animals and human beings, investigating how behaviour is associated to physical appearance. This topic was treated with considerable suspicion by the Roman Catholic Church which at this time was putting many works onto the Index of Forbidden Books. After a long wait of three years, the book was approved by the official censors. In the book he describes his own physical appearance but, as usual with della Porta, it is an idealised version at odds with the descriptions of others. He had a thin face with deep set bright eyes, a long irregularly shaped nose, and a distinctive high forehead.

Other topics he wrote on include chemistry in De distillatione (1609), mechanics, and squaring the circle in Elementa curvilineorum (1601). This work, described in detail by Hofmann in [13], uses Euclidean methods to study the areas bounded by circular arcs and straight lines. The main achievement is the proof that the sum of the two lunes of any right-angled triangle is equal to the area of the triangle, but della Porta then incorrectly deduces that each lune separately can be squared. Among his other achievements is a description of a steam engine in De' spiritali (1606) and being the first to recognise the heating effect of light rays.

The Accademia dei Lincei was founded in Rome in 1603 by Federico Cesi, inspired by della Porta's Magiae naturalis. The Academy's emblem, the sharp-eyed lynx, was taken from the title page of della Porta's book. The Preface of Magiae naturalis contains the words:-

... with lynx like eyes, examining those things which manifest themselves, so that having observed them, he may zealously use them.

Della Porta strongly encouraged Cesi in the setting up of his Academy and, in 1610, Cesi came down to Naples to set up a branch of the Accademia dei Lincei. Della Porta became president of the branch on 6 July 1610. During his final years, he suffered from ill health, particularly the fever that had regularly attacked him throughout his life, but also kidney stones which became progressively worse until he was bedridden.

Let us now look a little more at the twenty-volume 1584 edition of Magiae naturalis. Volume 17 deals with optics and the camera obscura is clearly described in Chapter 6. He was the first to propose adding a convex lens to the camera obscura. In Chapter 10, della Porta explains the use of concave and convex lenses. He writes:-

Concave lenses will make one see most clearly things that are afar off; but convexes, things near at hand; so you may use them as your sight requires. With a concave you will see small things afar off very clearly; with convex, things nearer appear bigger, bit more obscurely; if you know how to fit them together, you will see things afar off, and things near at hand, both greater and clearly. I have much helped some of my friends, who saw things afar off weakly; and what was near, confusedly, that they might see all things clearly.

After reading this passage, it is tempting to credit della Porta with inventing both telescopes and microscopes. However, the context of the passage is correcting defective vision so, although one still has to understand the importance of his optical work, one cannot give him the credit for telescopes and microscopes. We are left with trying to understand what he means by fitting together concave and convex lenses; perhaps that is the arrangement which today we think of as the fundamental property of Galileo's telescope, or perhaps della Porta is describing bifocal glasses. The situation is somewhat confused by an undated letter by della Porta, written after Galileo described his telescope, in which he claims to have been the first to invent the telescope. Certainly he studied refraction in De refractione, optices parte (1593), although he does not appear to have constructed a telescope before Galileo.

Volume 7 of Magiae naturalis deals with magnetism. In 1600 William Gilbert published his famous De magnete, a work which many claim to be the first modern work on experimental science. However, della Porta claimed that Gilbert:-

... took the whole seventh book of my 'Magiae naturalis' and split it into many books, making some changes; ... the material which he adds on his own account is false, perverse and melancholy; and towards the end he arrives at the mad idea that the earth is in motion.

We commented above that della Porta was well-known as a dramatist. He wrote three tragedies, twenty-nine comedies, and one tragi-comedy; only fourteen comedies, two tragedies and the tragi-comedy have survived. His most famous two plays are La sorella (The Sister) and Gli duoifratelli rivali (The Two Rival Brothers). The first of these is a [18]

... comedy intended to improve public morals by rigorously avoiding the anarchy and hedonism that had characterized so much of the comic theatre in Italy prior to the Counter-Reformation.

Louise Clubb writes about Gli duoifratelli rivali (see [11]):-

Della Porta seems to be testing the limits of 'commedia grave', stretching without breaking the rules of unity and decorum ... proceeding through deceits, disguises and bawdry to happy marriages, but also containing threats of death, dishonour, fratricide and governmental injustice, 'Fratelli rivali' remains commedia, but just barely.

Let us end by quoting della Porta's own words from the Prologue of Fratelli rivali:-

These works are judged rather by the universal applause of learned men of all nations; for they are seen printed in all parts of the world and translated into Latin, French, Spanish and various other languages; and the more they are heard and read, the more they please and are reprinted.