约翰·维恩John Venn

约翰·维恩的母亲Martha Sykes来自赫尔附近的Swanland，在他还很年幼时就去世了。他的父亲是Henry Venn牧师，在弗瑞兹·约翰出生时是赫尔附近Drypool教区的牧师。Henry Venn牧师本人是女王学院的会士，出身显赫家族。他的父亲，即约翰的祖父，是维恩牧师，曾任伦敦南部Clapham的牧师。他成为Clapham教派的领袖，这是一个以他的教堂为中心的福音派基督徒团体。他们成功开展了废除奴隶制的运动，倡导监狱改革和防止残忍运动，并支持海外传教工作。

不仅在福音派基督教运动中发挥重要作用的是维恩的祖父，他的父亲Henry Venn牧师也是如此。非洲和东方传教协会由英格兰教会的福音派神职人员于1799年创立，1812年更名为非洲和东方教会传教士协会。Henry Venn牧师于1841年成为该协会的秘书，为了履行职责，他搬到了伦敦附近的Highgate。他一直担任这一职务，直到1873年去世。

正如从他的家庭背景可以预料的那样，约翰受到了非常严格的教养，除了遵循家族传统成为神职人员之外，从未有过其他想法。他先是在海格特的罗杰·乔姆利爵士学校就读，然后进入伊斯灵顿私立预备学校。

当他于1853年10月进入剑桥大学冈维尔与凯厄斯学院时，他：-

……对各种书籍的了解如此之少，以至于可以说他是在那里才开始他的文学知识。

他在学习的第二年获得了数学奖学金，1857年以数学荣誉学位考试第六名数学荣誉学位考试一等及格者（Wrangler）毕业，这意味着在获得数学一等学位的学生中他排名第六。毕业后不久，他被选为冈维尔与凯厄斯学院的会士，两年后被任命为牧师。事实上，毕业后的第二年，即1858年，他已在伊利被任命为会吏，随后在被任命为牧师后，他先是在赫特福德郡的切森特担任助理牧师，然后在萨里郡的莫特莱克担任了一年助理牧师。

1862年，他回到剑桥大学担任道德科学讲师，学习和教授逻辑学和概率论。他已经对逻辑学、哲学和形而上学产生了兴趣，阅读了奥古斯塔斯·德摩根、乔治·布尔、约翰 Austin和约翰 Stuart Mill的论著。回到剑桥后，他发现自己与许多学者如艾萨克·托德夯特有共同的兴趣。他还在多年间对道德科学荣誉学位考试的发展发挥了重要作用。他讲授并主持该荣誉学位考试的考试，在讲师和学生之间营造了友好的氛围。

维恩扩展了乔治·布尔的数理逻辑，并以其用图示法表示集合及其并集和交集而为数学家和逻辑学家所熟知。他考虑三个圆盘$R, S$和$T$作为集合$U$的典型子集。这些圆盘及其补集的交集将$U$分成8个不重叠的区域，这些区域的并集给出了原始集合$R, S, T$的256种不同的Boolean组合。

维恩于1866年撰写了Logic of Chance，约翰·梅纳德·凯恩斯将其描述为：-

……极具原创性，并对统计学理论的发展产生了相当大的影响。

1867年，维恩与查尔斯·埃德蒙斯通牧师的女儿苏珊娜·卡内基·埃德蒙斯通结婚。他们有一个孩子，儿子约翰 Archibald Venn，他于1932年成为剑桥大学王后学院院长，并与父亲开展了重大合作研究项目，我们将在下文提供更多细节。

维恩于1881年发表了Symbolic Logic，1889年发表了The Principles of Empirical Logic。其中第二部作品原创性稍逊，但第一部被约翰·梅纳德·凯恩斯描述为：-

……可能是他在逻辑学方面最持久的著作。

1883年，维恩当选为皇家学会会士，同年被剑桥大学授予理学博士学位。大约此时，他的职业生涯改变了方向，因为就在他当选皇家学会会士的同一年，他离开了神职。他的儿子约翰Archibald Venn在Dictionary of National Biography中撰写了父亲的讣告，并解释了这一立场：-

长期以来，一位神职人员宣讲当时受限制的福音派信条，同时丝毫不虚伪地积极投身于哲学研究，已不再被视为异常；然而……发现自己与正统神职观点愈发不合，维恩便援引了《神职人员无行为能力法》。他天性思辨，后来常说，由于关于《三十九条信纲》的公认观点此后发生了变化，他本可以始终保留自己的圣职；事实上，他终其一生都是一个怀有真诚宗教信仰的人。

维恩的兴趣转向了历史，并通过在1888年将自己收藏的大量逻辑学书籍捐赠给剑桥大学图书馆来标志这一方向转变。他撰写了自己学院的历史，于1897年出版了The Biographical History of Gonville and Caius College 1349-1897，该书：-

……涉及在大学、主教及其他档案中进行大量艰苦而有条理的搜寻。

The annals of a clerical family（1904年）追溯了他自己家族的历史至十七世纪，并记载他是其家族中第八代接受大学教育的人。1910年，他出版了一部历史传记著作，即关于约翰凯厄斯的专论，凯厄斯是他所在学院的创始人之一。三年后，他出版了Early Collegiate Life，其中收录了他的许多作品，描述了剑桥大学早期生活的情形。随后，他承担了编纂剑桥大学历史Alumni Cantabrigienses的巨大任务，其第一卷于1922年出版。在这项任务中，他得到了儿子约翰Archibald Venn的协助，另一位历史学家如此描述这项工作：-

对于任何未曾目睹这项工作形成过程的人来说，很难意识到这项伟大事业所涉及的巨大研究量。

它是[3]：-

... 不亚于一份“从最早时期到1900年剑桥大学所有已知学生、毕业生和任职人员的传记名单”。... 文恩父子不遗余力地建立这些记录，它们对历史学家和系谱学家具有非凡的价值 ...

第一部分包含76,000个名字，涵盖至1751年的时期。在维恩去世时，涵盖1751年至1900年时期的第二部分以手稿形式存在，并包含另外60,000个名字。

维恩还有其他技能和兴趣，包括一项罕见的建造机器的技能。他利用自己的技能建造了一台投掷板球的机器，这台机器如此出色，以至于1909年澳大利亚板球队访问剑桥时，维恩的机器四次将其中一位顶级明星击出局。

他的儿子如此描述：-

他身材瘦削，一生都是优秀的步行者和登山者，热衷植物学，也是出色的谈话者和语言学家。

John Venn's mother, Martha Sykes, came from Swanland near Hull and died while he was still quite a young boy. His father was the Rev Henry Venn who, at the time of John's birth, was the rector of the parish of Drypool, near Hull. The Rev Henry Venn, himself a fellow of Queen's, was from a family of distinction. His father, John's grandfather, was the Rev John Venn who had been the rector of Clapham in south London. He became the leader of the Clapham Sect, a group of evangelical Christians centred on his church. They successfully campaigned for the abolition of slavery, advocated prison reform and the prevention of cruel sports, and supported missionary work abroad.

It was not only Venn's grandfather who played a prominent role in the evangelical Christian movement, for so did his father the Rev Henry Venn. The Society for Missions in Africa and the East was founded by evangelical clergy of the Church of England in 1799 and in 1812 it was renamed the Church Missionary Society for Africa and the East. The Rev Henry Venn became secretary to this Society in 1841 and in order to carry out his duties moved to Highgate near London. He held this position until his death in 1873.

As might be expected from his family background, John was very strictly brought up, and there was never any thought other than that he would follow the family tradition into the priesthood. He attended first Sir Roger Cholmley's School in Highgate, then the private Islington Preparatory School.

When he entered Gonville and Caius College Cambridge in October 1853 he had:-

... so slight an acquaintance with books of any kind that he may be said to have begun there his knowledge of literature.

Having been awarded a mathematics scholarship in his second year of study, he graduated as sixth Wrangler in the Mathematical Tripos of 1857, meaning that he was ranked in the sixth place out of those students who were awarded a First Class degree in mathematics. He was elected a Fellow of Gonville and Caius College shortly after graduating, and two years later was ordained a priest. In fact the year after his graduation, in 1858, he had been ordained a deacon at Ely, then after his ordination as a priest he had served as a curate first at Cheshunt, Hertfordshire, and then for a year as a curate at Mortlake, Surrey.

In 1862 he returned to Cambridge University as a lecturer in Moral Science, studying and teaching logic and probability theory. He had already become interested logic, philosophy and metaphysics, reading the treatises of De Morgan, Boole, John Austin, and John Stuart Mill. Back at Cambridge he now found interests in common with many academics such as Todhunter. He also played a large role in developing the Moral Sciences Tripos over many years. He lectured and examined the Tripos, developing a friendly atmosphere between the lecturers and the students.

Venn extended Boole's mathematical logic and is best known to mathematicians and logicians for his diagrammatic way of representing sets, and their unions and intersections. He considered three discs $R, S$, and $T$ as typical subsets of a set $U$. The intersections of these discs and their complements divide $U$ into 8 non-overlapping regions, the unions of which give 256 different Boolean combinations of the original sets $R, S, T$.

Venn wrote Logic of Chance in 1866 which Keynes described as:-

... strikingly original and considerably influenced the development of the theory of statistics.

In 1867 Venn married Susanna Carnegie Edmonstone, the daughter of the Rev Charles Edmonstone. They had one child, a son John Archibald Venn, who became president of Queen's College, Cambridge, in 1932, and undertook major collaborative research projects with his father that we give more details on below.

Venn published Symbolic Logic in 1881 and The Principles of Empirical Logic in 1889. The second of these is rather less original but the first was described by Keynes as:-

... probably his most enduring work on logic.

In 1883 Venn was elected a Fellow of the Royal Society and in the same year was awarded a Sc.D. by Cambridge. About this time his career changed direction for in the same year that he was elected to the Royal Society, he left the priesthood. His son, John Archibald Venn, wrote his father's obituary in the Dictionary of National Biography and explained the position:-

It had long ceased to be regarded as an anomaly for a clergyman to preach the then circumscribed evangelical creed and at the same time, without the slightest insincerity, to devote himself actively to philosophical studies; yet ... finding himself still less in sympathy with the orthodox clerical outlook, Venn availed himself of the Clerical Disabilities Act. Of a naturally speculative frame of mind, he was want to say later that, owing to subsequent change in accepted opinion regarding the Thirty-nine Articles, he could consistently have retained his orders; he remained, indeed, throughout his life a man of sincere religious conviction.

Venn's interest turned towards history and he signalled this change in direction by donating his large collection of books on logic to the Cambridge University Library in 1888. He wrote a history of his college, publishing The Biographical History of Gonville and Caius College 1349-1897 in 1897, which:-

... involved a vast amount of painstaking and methodical search among university, episcopal, and other records.

The annals of a clerical family (1904) trace the history of his own family back to the seventeenth century and record that he was the eighth generation of his family to have a university education. In 1910 he published a work on historical biography, namely a treatise on John Caius, one of the founders of his College. Three years later he published Early Collegiate Life which collected many of his writings describing what life was like in the early days of Cambridge University. He then undertook the immense task of compiling a history of Cambridge University Alumni Cantabrigienses, the first volume of which was published in 1922. He was assisted by his son John Archibald Venn in this task which was described by another historian in these terms:-

It is difficult for anyone who has not seen the work in its making to realise the immense amount of research involved in this great undertaking.

It was [3]:-

... nothing less than a "biographical list of all known students, graduates, and holders of office at the University of Cambridge from the earliest times to 1900". ... The Venns, father and son, spared no industry in building up these records, which are of extraordinary value to historians and genealogists ...

The first part contained 76,000 names and covered the period up to 1751. At the time of Venn's death the second part, covering the period from 1751 to 1900, existed in manuscript and contained a further 60,000 names.

Venn had other skills and interests too, including a rare skill in building machines. He used his skill to build a machine for bowling cricket balls which was so good that when the Australian Cricket team visited Cambridge in 1909, Venn's machine clean bowled one of its top stars four times.

His son gives this description:-

Of spare build, he was throughout his life a fine walker and mountain climber, a keen botanist, and an excellent talker and linguist.