David Hume
（1711.4.26-1776.8.25）

大卫·休谟（1711—1776）在他的心理学作品中也给哲学和心理学带来了很大的麻烦。首先，让我们认识一下这位苏格兰复兴运动中最耀眼的明星。

在苏格兰，如在西方世界其它地方一样，复兴运动是18世纪流行的哲学运动，其特征是对科学和理智的依靠，对传统宗教的质疑和对全球人类进步的信仰。休谟在童年时代从两个方面看不出他怎么有可能成为这个运动的权威人士：他出生在爱丁堡一个优越的长老会家庭，在童年时代就接受了卡尔文教的神学观点。作为一个小孩，他看上去很木讷（他自己的母亲说他是个“很精细，天性良好的火山口，但是，脑袋瓜子却不怎么灵”），不过，这种木讷有可能是因为他的迟钝和身体过重的倾向而造成的错误印象；他很聪明，12岁就进了爱丁堡大学。至于他的卡尔文主义，在15岁的时候，他已经就在热切地阅读他那个时代的哲学著作，而到18岁的时候，他已经就成了卡尔文主义的叛教者。后来论及此事的人说：“自从他开始阅读洛克和克拉克的作品以后，他就从来没有得到过任何信仰的快乐了。”

休谟是家里的第二个孩子，只继承了很少的遗产。他因此而攻读法律，可一点也不喜欢法律，以至于后来差点精神失常。他觉得商人办公室里的吝啬也同样难以忍受。23岁时，他决定靠当哲学家谋点饭吃，因而去法国谋个便宜生计。他在拉弗莱奇安顿下来（笛卡儿曾在这里学习过），然后，虽然没有能够上大学，可他终于说服了耶酥会，让他使用这里的图书室。仅在两年时间内，他就完成了他的两卷本《人类天性论：实验（牛顿）推理法引入道德主题的尝试》（1738年），在这部著作里，他第一次引入了自己的心理学。

他原指望这本书能带给他巨大名声的，可当这本书几乎没有引起任何人的注意时，他感到痛心万分。

（后来，他又重写此书，改成更简单一些的形式，效果稍为好些了。）

他被迫谋一个生计，因而给一位年轻人当了一阵子辅导教师，然后成了詹姆斯·圣克莱将军的私人秘书。在这个岗位上，他有了一份不错的收入，穿上了红色的制服，吃得好，慢慢发胖了。一位访问者描述他说，他生就一张又宽又胖的脸．“除了愚钝以外，脸上没有任何表情”，而且他的身材更像是一位地方官员，而不像一位精细的哲学家。可是，人不可貌相，海不可斗量，相貌有时候是骗人的，休谟不多久就存足了一笔钱，可以专心写作了。他成熟年代创作的政治、经济、哲学、历史和宗教著作给他带来了梦寐以求的名声。在法国，虽然他长得腰圆体胖，可很快便成了各个沙龙的座上宾，而且得到伏尔泰和狄德罗的称赞。在伦敦，他的家成了沙龙，亚当?史密斯和其他一些自由主义思想家经常光顾他家，大家一起高谈阔论，无话不说。

朋友和熟人认为他很聪明，很友善，从善如流，极有耐心，他对自己也是这么看的，他还说自己“是个宠辱不惊，自有城府的人。”（他23岁的时候让一位年轻妇女怀孕了，在37岁时双膝跪下追求一位有夫之妇的伯爵夫人，未果。）虽然他不喜欢斯宾诺莎，因为他是位无神论者，可是，他自己到底也还是位怀疑论者。波士威尔在他因直肠癌而卧床垂死时问他说，他现在是否不相信有一个来世在那里，休谟回答说，那是一个“最没有理智的幻想”。说到底，休谟是位彻底的复兴主义者。

休谟写作《人类天性论》的主要目的是要开拓出一套基于“有关人的科学”的道德哲学来，指的实际上是心理学。因此，他努力建立了一个人类激情和我们对激情的看法的理论，这就使得他要去了解，我们的思想来自何处。他以一位真正的经验主义者的方法来探索这个问题：“因为有关人的科学才是其它科学惟一坚实的基础，因此，我们能够给这门科学本身的坚实基础就必须以经验和观察为基础。”

当然，尽管休谟大量引用和批评了其他人的作品，但他最主要的依靠还是自己的内省式观察。作为一位彻底的经验主义者，他不容分说地排斥了所有有关非物质灵魂的本质的问题──对笛卡儿来说一度是如此重要的那个会思想的“我”──他宣布，灵魂的本质是“一个非智力的问题”，根本就不值得讨论。他自己对这个有意识能力的自我的看法是以对他本人的思想过程仔细的观察为基础的，他认为，思维完全是感觉构成的：

“当我以非常私密的态度进入这个我叫做自我的东西里面时，我总是会不小心跌落在这个或那个特殊的感觉上面，或冷或热，或明或暗，或爱或恨，或痛苦，或快乐……我斗胆妄言，全体的人类也莫不如此，他们也不过是一大堆不同感觉而已。”

休谟在“印象”（即他表示感觉或感知的用词）和“思想”（同样的一些经验，但实体不在场，比如在回忆中、思考中，还有在梦中）之间作了区分。跟洛克一样，他说，这些简单的元素是一些复杂和抽象的思想形成的构件。可是，以什么方式呢？在这里，他远远走在比洛克更远的地方了。必须有个“联合的原理”，他推想，这个原理采取三种形式：“一些品质，即这种联想所产生的东西，通过这些东西，并以这种方式，思维被从一种思想传递至另一种思想，这些品质就是三个东西，即，在时间和空间上的相似性、连续性以及因和果。”

通过这种联想，或者通过这三种特性而合并起来的思想，在休谟看来是思维的基本原则，它对其运作的重要性可与地心引力对星球的运动的重要性一样。他甚至还把联想称作“一种吸引”，它使思想互相连接起来。因此，在联想这一点上，他比洛克认识得深刻些，因为洛克依靠联想时，主要是为了解释思想之间不正常的联接，但不认为它是普遍的精神过程。到目前为止尚且无事。可是，尽管休谟确信他自己已经找到了思维的基本科学法则，他还是进而削弱了这门科学本身的基础，因为他对联想的三种力量之一进行了解释，即何为因果。他并没有像常说的那样宣称没有因果的存在；可是，他的确说过．我们无法直接体验因果关系，因而就不知道它是什么东西，甚至也无法证明它的确就存在着。我们只知道，有些现象好像总是，或者几乎总是紧跟着另一个现象，我们因此就推断，是第一个现象引起了第二个现象。可是，这只是基于对这两种现象之间的联想而产生的一种期盼：“因和果的想法是从经验中得来的，它告诉我们说，这些特别的物体，在过去所有的情况下，一直都是彼此联系在一起的……我们所有涉及到因果的推理，都不过是从习惯而来的，而非来自别的任何东西。”

因果关系只不过是思维的习惯。我们没有也不能以基本的感官感觉来体验或者感知到它；我们只知道，当一件事情发生时，另一件事情也会发生。要预测事情总是这样的，那就会犯一个错误；我们只能推断，当甲发生时，乙有可能会紧跟而来。休谟作出结论说，我们之所以相信因果关系的存在，相信外部世界的存在，并不是因为我们真正知道它们的确存在，而是因为他所提出的怀疑观太难令人相信了：

“不管依靠什么方法，要为我们自己的理解或者为我们的感觉而辩护都是不可能的……当怀疑的疑团很自然地从对这些主体深刻而缜密的思考中升起时，我们越想越会产生更多的怀疑，不管是肯定还是否定它。粗心大意或者漫不经心可能会给我们一个解决办法。因为这个原因，我就完全依靠它们，而且，不管读者此时的观点是什么，我都坚信，他在这里被说服的一个小时既是外部的世界，亦是内部的世界。”休谟对因果关系概念的摧毁性攻击在科学史上具有重大的意义，尤其是在心理学史上，因为，在心理学努力成为科学的途中，它一直都在努力地发现精神的因果法则。休谟时代和后世的一些心理学家因而就相信，心理学不可能得出因果解释，因而就应该只对付相互之间的关系──即两件事情会持续同时发生或者先后发生这样的可能性。可笑的是，休谟有意让它们成为他道德系统的基础之经验主义和联想主义留存了下来，而他的道德系统，即一种温和的功利主义，却早已成为过眼烟云，一去而不复返了。

 
大卫·休谟

钱钟书

J.Y.T.Greig(John Carruthers): David Hume (格莱格:《大卫休谟传》），London:cape。一九三一年。四百三十六页。十六先令。


这几年来，休谟似乎又交上好运了，试看，关于他的哲学和他的生平的书接连地出版。是六十年前罢，那时格林（T. H. Green)为休谟的全集做了两篇传诵一时的“引论”，指桑骂槐地借着攻击休谟来攻击穆勒和斯宾塞尔，把休谟批评得体无完肤；从此，休谟的声名立刻低落下去，而格林的声名忽然地响起来了。格林劝二十五岁以下的青年，专读康德和黑格尔，而丢开斯宾塞尔和穆勒！当然，他不好意思说丢开洛克和休谟。六十年来，斯宾塞尔和穆勒诚然是“束置高阁”(On a shelf)了；康德和黑格尔呢？谢谢格林和凯尔德(Caird)的鼓噪，已经风弥英国了；但是，被打倒的休谟居然翻过身来了；而格林自己呢？时髦的唯心论者一手拉拢爱因斯坦，一手拉拢柯罗采了；甚而至于卜赖德雷的书，也是驳的多，读的少了，而格林呢？Qù sont les neiges d'antan?

我常想，格林和休谟间的关系，并不如一般哲学史家和唯心论者甚而至于格林自己所想的那样格格不相容。据我看来，格林其实是承受休谟的知识论的衣钵的。何所见而云然？即于格林讲“知识中之精神原理”见之。因为格林不知不觉地接受了休谟对于知识的解析——一切感觉是零零碎碎的，不相联系的——所以他才那样发急，特地(ad hoc)把“精神原理”介绍进来，为这许多不联属的，零碎的感觉拉拢。假使格林像詹美士那样批评休谟——根本反对是感觉不联属的，零碎的，那么，“精神原理”便不需要了，至少在知识论上。这岂不是强有力的反证么？世苟有鲍桑癸，欲续作《现代哲学中之冤家碰头记》（The Meeting of Extremes in Contemporary Philosophy）者，愿以休谟与格林之Rapprochement 质之。

休谟之所以不朽，诚然是因为他的哲学。但是，他是一个多才多艺的人，不仅以哲学自限。于哲学家头衔之外，他还有许多旁的头衔，例如：史家，文家，政治家，经济家，卖空买空的商人，猪——“伊壁鸠鲁豚笠中最肥的猪”，像史家吉朋在某处说过的，因为休谟的食不厌精(Gourmet)和脍不厌“巨”(Gourmand)。他的时代，又是历史上最有趣的时代——十八世纪。他又曾寄居于那个时代中最有趣的国——革命前的法国，而又与法国中最有趣的人——卢梭往来。其生活之丰富，可想而知。

通行英国的“文人丛书”中的《休谟传》，虽出赫胥黎之手，只把三四十页了却休谟的一生，当然不会翔实。格莱格教授居然详详细细地花了四百余页来专记休谟的行事，我们看了已经够高兴了，何况教授的文章是这样的轻灵呢？

作者为文学批评家，苏格兰人，而生长于中国的东三省；自今年起，在南非洲Witwater Srand大学任英国文学教授，除为休谟作详传外，并且编辑过他的书信集（此书张申府先生《新哲学》书中曾介绍过）。此传专记生平，并不批评学理；叙述虽十分生动，而事实却都有根据(Documented)。看惯Strachey-Maurois-Ludwig派所作的传记的人，也许觉得本书欠“刺激性”。但是，本书的目的是叙述而非描写，所以（一）不“踵事增华”，（二）不卖弄才情——像Charles Smith 在 Historical Biography中所指摘Strachey-Maurois-Ludwig派那样的做。然而本书中像描写苏格兰教堂中做礼拜的情形，休谟与巴黎贵妇演戏时的窘状 (“Eh bien, mesdemoiselles, vous voilà donc”)，休谟与卢梭伦敦看戏的盛况，等等，其有趣味正不亚于小说。

从来批评休谟的人，总说他名心 (Vanity)太重，例如 Taylor教授在《休谟与不可思议》演讲中，Selby-Bigge爵士在《人知探究》引论内。赫胥黎甚至痛斥休谟为好名一念所误，不专攻哲学。但是，从格莱格教授看来，休谟根本上是一个讲实际而不重虚想的人。像《人性论》那样大著不过是休谟少年未入世以前的“超超玄著”。休谟中年后的讲史学，讲政治，讲经济，改《人性论》为《人知探究》，并非想“曲学阿世，哗众取宠”，像赫胥黎所说，而实出于其求实用的脾气。这一点的确是于休谟的人格的解释上极重大的贡献。然而我们看到休谟这样的讲实用，终不免被《哲学家的心理》的作者Hertzberg博士置之Professional failure之例，我们不自主地想到Granscendental irony了！

本书作者虽没有综括地说明休谟是怎样的人，休谟却会把自己的特征分为十六项。摘译数则，使读者可想像休谟的风趣：（一）好人而以做坏事为目的；（三）非常用功，但是无补于人而亦无益于已；（八）非常“怕难为情”，颇谦虚，而绝不卑逊；（十一）虽离群索居而善于应酬；（十三）有热诚而不信宗教，讲哲学而不求真理；（十四）虽讲道德，然不信理智而信本能；（十五）好与女子调情，而决不使未嫁的姑娘的母亲发急，或已嫁的姑娘的丈夫拈酸。

本书第一章为休谟哲学之简单说明。虽无特见，而其称赞黎德(Reid)，颇足注意。作者的苏格兰人的特色，此处极看得出。苏格兰人最深于地域观念，讲到驳休谟的怀疑论的人，总要抬出黎德来和康德相比——已故Andrewseth的《苏格兰哲学》那本书就是一个好例。

David Hume

（选自斯坦福百科全书）

Generally regarded as the most important philosopher ever to write in English, David Hume (1711-1776) -- the last of the great triumvirate of "British empiricists" -- was also noted as an historian and essayist. A master stylist in any genre, Hume's major philosophical works -- A Treatise of Human Nature (1739-1740), the Enquiries concerning Human Understanding (1748) and concerning the Principles of Morals (1751), as well as the posthumously published Dialogues concerning Natural Religion (1779) -- remain widely and deeply influential, despite their being denounced by many of his contemporaries as works of scepticism and atheism. While Hume's influence is evident in the moral philosophy and economic writings of his close friend Adam Smith, he also awakened Immanuel Kant from his "dogmatic slumbers" and "caused the scales to fall" from Jeremy Bentham's eyes. Charles Darwin counted Hume as a central influence, as did "Darwin's bulldog," Thomas Henry Huxley. The diverse directions in which these writers took what they gleaned from reading Hume reflect not only the richness of their sources but also the wide range of Hume's empiricism. Comtemporary philosophers recognize Hume as one of the most thoroughgoing exponents of philosophical naturalism.

Life and Works
Born in Edinburgh, Hume spent his childhood at Ninewells, the family's modest estate on the Whitadder River in the border lowlands near Berwick. His father died just after David's second birthday, "leaving me, with an elder brother and a sister under the care of our Mother, a woman of singular Merit, who, though young and handsome, devoted herself to the rearing and educating of her Children." (All quotations in this section from Hume's autobiographical essay, "My Own life", reprinted in HL.)

Katherine Falconer Home realized that young David was "uncommonly wake-minded" -- precocious, in her lowland dialect -- so when his brother went up to Edinburgh University, David, not yet twelve, joined him. He studied mathematics and contemporary science, and read widely in history, literature, and ancient and modern philosophy.

Hume's family thought him suited for a career in the law, but he preferred reading classical authors, especially Cicero, whose Offices became his secular substitute for The Whole Duty of Man and his family's strict Calvinism. Pursuing the goal of becoming "a Scholar & Philosopher," he followed a rigorous program of reading and reflection for three years until "there seem'd to be open'd up to me a New Scene of Thought."

The intensity of developing this philosophical vision precipitated a psychological crisis in the isolated scholar. Believing that "a more active scene of life" might improve his condition, Hume made "a very feeble trial" in the world of commerce, as a clerk for a Bristol sugar importer. The crisis passed and he remained intent on articulating his "new scene of thought." He moved to France, where he could live frugally, and settled in La Flèche, a sleepy village in Anjou best known for its Jesuit college. Here, where Descartes and Mersenne studied a century before, Hume read French and other continental authors, especially Malebranche, Dubos, and Bayle; he occasionally baited the Jesuits with iconoclastic arguments; and, between 1734 and 1737, he drafted A Treatise of Human Nature.

Hume returned to England in 1737 to ready his Treatise for the press. To curry favor with Bishop Butler, he "castrated" his manuscript, deleting his controversial discussion of miracles, along with other "nobler parts." Book I (Of the Understanding) and Book II (Of the Passions) was published anonymously in 1739. Book III (Of Morals) appeared in 1740, as well as an anonymous Abstract of the first two books of the Treatise. Although other candidates, especially Adam Smith, have occasionally been proposed as the Abstract's author, scholars now agree that it is Hume's work. The Abstract features a clear, succinct account of "one simple argument" concerning causation and the formation of belief. Hume's elegant summary presages his "recasting" of that argument in the first Enquiry.

The Treatise was no literary sensation but it didn't "fall dead-born from the press," as Hume disappointedly described its reception. Despite his surgical deletions, the Treatise attracted enough of a "murmour among the zealots" to fuel his life-long reputation as an atheist and a sceptic.

Back at Ninewells, Hume published two modestly successful volumes of Essays, Moral and Political in 1741 and 1742. When the Chair of Ethics and Pneumatical ("Mental") Philosophy at Edinburgh became vacant in 1745, Hume hoped to fill it, but his reputation provoked vocal and ultimately successful opposition. Six years later, he stood for the Chair of Logic at Glasgow, only to be turned down again. Hume never held an academic post.

In the wake of the Edinburgh debacle, Hume made the unfortunate decision to accept a position as tutor to the Marquess of Annandale, only to find that the young Marquess was insane and his estate manager dishonest. Hume managed to extricate himself from this situation, and accepted the invitation of his cousin, Lieutenant-General James St. Clair, to be his Secretary ("I wore the uniform of an officer.") on a military expedition against the French in Quebec. Contrary winds delayed St. Clair's fleet until the Ministry canceled the plan, only to spawn a new expedition that ended as an abortive raid on the coastal town of L'Orient in Brittany.

Hume also accompanied St. Clair on an extended diplomatic mission to Vienna and Turin in 1748. While he was in Italy, the Philosophical Essays concerning Human Understanding appeared. A recasting of the central ideas of Book I of the Treatise, the Philosophical Essays were read and reprinted, eventually becoming part of Hume's Essays and Treatises under the title by which they are known today, An Enquiry concerning Human Understanding. In 1751, this Enquiry was joined by a second, An Enquiry concerning the Principles of Morals. Hume described the second Enquiry, a substantially rewritten version of Book III of the Treatise, as "incomparably the best" of all his works. More essays, the Political Discourses, appeared in 1752, and Hume's correspondence also reveals that a draft of the Dialogues concerning Natural Religion was underway at this time.

An offer to serve as Librarian to the Edinburgh Faculty of Advocates gave Hume the opportunity to work steadily on another project, a History of England, which was published in six volumes in 1754, 1756, 1759, and 1762. His History became a best-seller, finally giving him the financial independence he had long sought.

But even as a librarian, Hume managed to arouse the ire of the "zealots." In 1754, his order for several "indecent Books unworthy of a place in a learned Library" prompted a move for his dismissal, and in 1756, an unsuccessful attempt to excommunicate him. The Library's Trustees canceled his order for the offending volumes, which Hume regarded as a personal insult. Since he needed the Library's resources for his History, Hume did not resign his post; he did turn over his salary to Thomas Blacklock, a blind poet he befriended and sponsored. When research for the History was done in 1757, Hume quickly resigned to make the position available for Adam Ferguson.

Hume's publication of Four Dissertations (1757) was also surrounded by controversy. In 1755, he was ready to publish a volume that included "Of Suicide" and "Of the Immortality of the Soul." He suppressed the controversial essays when his publisher, Andrew Millar, was threatened with legal action, due largely to the machinations of the minor theologian William Warburton. Hume added "Of Tragedy" and "Of the Standard of Taste" to round out the volume, which also included The Natural History of Religion and A Dissertation on the Passions.

In 1763, Hume accepted an invitation from Lord Hertford, the Ambassador to France, to serve as his Private Secretary. During his three years in Paris, Hume became Secretary to the Embassy and eventually its Chargè d'Affaires. He also become the rage of the Parisian salons, enjoying the conversation and company of Diderot, D'Alembert, and d'Holbach, as well as the attentions and affections of the salonnières, especially the Comtesse de Boufflers.

Hume returned to England in 1766, accompanied by Jean-Jacques Rousseau, who was then fleeing persecution in Switzerland. Their friendship ended quickly and miserably when the paranoid Rousseau became convinced that Hume was masterminding an international conspiracy against him.

After a year (1767-68) as an Under-Secretary of State, Hume returned to Edinburgh to stay. His autumnal years were spent quietly and comfortably, dining and conversing with friends, and revising his works for new editions of his Essays and Treatises, which contained his collected essays, the two Enquiries, A Dissertation on the Passions, and The Natural History of Religion. In 1775, he added an "Advertisement" to these volumes, in which he appeared to disavow the Treatise. Though he regarded this note as "a compleat Answer" to his critics, especially "Dr. Reid and that biggotted, silly fellow, Beattie," subsequent readers have wisely chosen to ignore Hume's admonition to ignore his greatest philosophical work.

Upon finding that he had intestinal cancer, Hume prepared for his death with the same peaceful cheer that characterized his life. He arranged for the posthumous publication of his most controversial work, the Dialogues concerning Natural Religion; it was seen through the press by his nephew and namesake in 1779, three years after his uncle's death.

The Treatise and the Enquiries
Hume's apparent disavowal of the Treatise raises a question as to how we should read his works. Should we take his "Advertisement" literally and let the Enquiries represent his considered view? Or should we take him seriously and conclude -- whatever he may have said or thought -- that the Treatise is the best statement of his position?

Both responses presuppose that there are substantial enough differences between the works to warrant our reading them as disjoint. This is highly dubious. Even in the "Advertisement," Hume says that "most of the principles, and reasonings, contained in this volume, were published" in the Treatise, and that he has "cast the whole anew in the following pieces, where some negligences in his former reasoning and more in the expression, are...corrected" (EHU, "Advertisement"). Despite his protests, this hardly sounds like the claims of one who has genuinely repudiated his earlier work.

Hume reinforced this perspective when he wrote Gilbert Elliot of Minto that "the philosophical principles are the same in both...by shortening and simplifying the questions, I really render them much more complete" (HL, I:158). And in "My Own Life," he opined that the Treatise's lack of success "proceeded more from the manner than the matter." Hume's "recasting" of the Treatise was probably designed primarily to address this point. This brief overview of Hume's central views on method, epistemology, and ethics therefore follows the structure -- "the manner" -- of the Enquiries and emphasizes "the matter" they have in common with the Treatise.

Method
In his Introduction to the Treatise, Hume bemoans the sorry state of philosophy, evident even to "the rabble without doors," which has given rise to "that common prejudice against metaphysical reasonings of all kinds" (T, xiv). He hopes to correct this miserable situation by introducing "the experimental method of reasoning into moral subjects," establishing "a science of human nature" that will put philosophy on a "solid foundation" of "experience and observation" (T, Introduction).

Hume's positive, naturalistic project has much in common with contemporary cognitive science. Recent readers have paid more attention to these aspects of his philosophy than his earlier critics apparently did. As a result, no contemporary Hume scholar entirely accepts the traditional view that Hume was solely a negative philosopher whose goal was to make manifest the sceptical consequences of the views of his empiricist predecessors. But there remains considerable disagreement about the role and extent of scepticism in his philosophy, and disagreement about its relation to the naturalistic elements of his system. What Hume says about his aims and method helps clarify these issues.

In An Enquiry concerning the Principles of Morals, Hume says that he will "follow a very simple method," which will nonetheless bring about "a reformation in moral disquisitions" like that already accomplished in natural philosophy, where we have been cured of "a common source of illusion and mistake" -- our "passion for hypotheses and systems." To make parallel progress in the moral sciences, we should "reject every system...however subtle or ingenious, which is not founded on fact and observation," and "hearken to no arguments but those which are derived from experience" (EPM, 173-175).

The "hypotheses and systems" Hume rejects cover a wide range of philosophical and theological views. These theories were too entrenched, too influential, and too different from his proposed science of human nature to permit him just to present his "new scene of thought" as their replacement. He needed to show why we should reject these theories, so that he might have space to develop his own.

Hume outlines this strategy in the first section of An Enquiry concerning Human Understanding. He considers two prominent types of "false metaphysics" (EHU, 12). Though each type has as its basis an appealing human characteristic, both views extend their accounts of these characteristics beyond their basis in experience, and so beyond the bounds of cognitive content.

The first view looks at humans as active creatures, driven by desires and feelings. It paints a flattering picture of human nature, easy to understand and even easier to accept. These philosophers make us feel what they say about our feelings, and what they say is so useful and agreeable that ordinary people who encounter these views are readily inclined to accept them. This view might be called sentimentalism. It is a generic characterization of the position defended in Hume's time by Shaftesbury and Francis Hutcheson.

The other view downgrades sentiment to concentrate on rationality, which it treats as the distinctive human characteristic. This view glorifies the reasonable aspects of our natures and appeals to them in its emphasis on rarefied speculation and abstract argument. The systems of Descartes and other rationalist philosophers fit this general description. Given its emphasis on the role of the intellect, this view might be called intellectualism.

Intellectualism and sentimentalism seem to be exhaustive alternatives, ways of characterizing the ancient debate as to whether reason or passion is, or should be, the dominant force in human life. Hume saw that both approaches capture important aspects of human nature, but that neither tells the whole story. We are active and reasonable creatures. A view that mixes both styles of philosophy will be best, so long as it gets the mixture right.

But getting the mixture right, Hume realized, is no easy task. Intellectualism is too abstract, too remote from ordinary life to have any practical application. It can indulge the worst excesses of human vanity, especially when it treats matters that are beyond the limits of human understanding. It can be co-opted by popular superstitions, peddling religious fears and prejudices cloaked in profound-sounding but meaningless metaphysical jargon.

It is tempting to react to these features of intellectualism by arguing that we should abandon metaphysics altogether. But ordinary life doesn't equip us to do good metaphysics, and without some measure of accurate metaphysical description, sentimentalism can't be as precise as it should be. Delicate sentiment requires just reasoning, and an adequate account of just reasoning requires an accurate and precise metaphysics. The only way to correct sentiment and to avoid the sources of error and uncertainty rooted in intellectualism, is to do more metaphysics -- but of the right kind. We must pursue true metaphysics if we want to jettison these false and deceptive views.

Hume's insight was to see that getting the correct mixture requires a two-fold task, with negative and positive aspects. To develop a science of human nature, it is first necessary to undermine the foundations of all forms of false and misleading metaphysics. When we are rid of these sources of superstition, prejudice, and error, the stage will be clear for the kind of mental geography that constitutes true metaphysics. Accurate, just reasoning about human nature -- the descriptive project of true metaphysics -- requires us to examine the scope and limits of our cognitive capacities, so that we may at last obtain an exact picture of the powers and limitations of human understanding.

The negative phase of Hume's project scrutinizes the central arguments of the dominant philosophical and theological views of his day and exposes the lack of cognitive content in their key notions. Hume's sceptical arguments are an important part of this negative phase. Since these arguments are among the most prominent and powerful Hume has to offer, it is not surprising that they are often mistaken for his final view. But these arguments function as reductios of theories he rejects, not as parts of the positive position he offers in their place. They point up the poverty of false metaphysics to rid us of the temptation of doing metaphysics this way. Only then will we be ready for the positive phase -- true metaphysics, which will replace the old incoherent metaphysics with the careful accurate description that is the proper goal of philosophy.

Empiricism
This combination of negative and positive aims is a distinguishing feature of Hume's particular brand of empiricism, and the strategy he devised to achieve these aims is revelatory of his philosophical genius. For Hume, all the materials of thinking -- perceptions -- are derived either from sensation ("outward sentiment") or from reflection ("inward sentiment") (EHU, 19). He divides perceptions into two categories, distinguished by their different degrees of force and vivacity. Our "more feeble" perceptions, ideas, are ultimately derived from our livelier impressions(EHU, Section II).

Although we permute and combine ideas in imagination to form complex ideas of things we haven't experienced, our creative powers extend no farther than "the materials afforded us by the senses and experience." Complex ideas are composed of simple ideas, which are fainter copies of the simple impressions from which they are ultimately derived, to which they correspond and exactly resemble. Hume offers this "general proposition" as his "first principle...in the science of human nature" (T, 7). Usually called the "Copy Principle," Hume's distinctive brand of empiricism is often identified with his commitment to it.

Hume presents the Copy Principle as an empirical thesis. He emphasizes this point by offering, in both the Treatise and the first Enquiry, as an empirical counterexample to the principle, "one contradictory phenomenon" (T, 5-6; EHU, 20-21) -- the infamous missing shade of blue. Hume asks us to consider "a person to have enjoyed his sight for thirty years, and to have become perfectly well acquainted with colours of all kinds, excepting one particular shade of blue..."(T, 6). Then

"Let all the different shades of that colour, except that single one, be plac'd before him, descending gradually from the deepest to the lightest; 'tis plain, that he will perceive a blank, where that shade is wanting, and will be sensible, that there is a greater distance in that place betwixt the contiguous colours, than in any other. Now I ask, whether 'tis possible for him, from his own imagination, to supply this deficiency, and raise up to himself the idea of that particular shade, tho' it had never been conveyed to him by his senses? I believe there are few but will be of the opinion that he can; and this may serve as a proof, that the simple ideas are not always derived from the correspondent impressions; tho' the instance is so particular and singular, that 'tis scarce worth our observing, and does not merit that for it alone we should alter our general maxim" (T 6). Hume's critics have objected that, in offering this counterexample, he either unwittingly destroys the generality of the Copy Principle, which he needs, given the uses to which he will put it, or else his dismissive attitude toward the counterexample reflects his disingenuous willingness to apply the Copy Principle arbitrarily, while pretending that it really possesses the generality his uses of it require.

Hume's defenders, on the other hand, maintain either that he should have granted that the imaginative construction of the missing shade really produces a complex idea, or that he should have insisted that such counterexamples are exceedingly rare, and that the contentious metaphysical ideas, the cognitive content of which he uses the Copy Principle to critique, are not possibly ideas that could be generated by the imagination in the way the missing shade is supposedly generatred.

These defenses have their attractive points, but there is a far more satisfying resolution of the issue the missing shade raises available to Hume. In Book II of the Treatise, he describes a similar remarkably similar phenomenon that occurs with certain passions:

"Ideas may be compar'd to the extension and solidity of matter, and impressions, especially reflective ones, to colours, tastes, smells and other sensible qualities. Ideas never admit of a total union, but are endow'd with a kind of impenetrability, by which they exclude each other, and are capable of forming a compound by their conjunction, not by their mixture. On the other hand, impressions and passions are susceptible of an entire union; and like colours, may be blended so perfectly together, that each of them may lose itself, and contribute only to vary that uniform impression, which arises from the whole. Some of the most curious phaenomena of the human mind are deriv'd from this property of the passions" (T 366).

In these cases of "impressions and passions," both of which are simples for Hume, two impressions or two passions are blended to form a third, which is also a simple impression or passion. It seems plausible to think, and Hume's language in this passage certainly suggests as much, that one's ideas of two shades of (say) blue could also be blended to produce a third simple idea -- an idea of the missing shade.

While Hume's empiricism is usually identified with the Copy Principle, it is actually his use of its reverse in his account of definition that is really the most distinctive element of his empiricism.

Believing that "the chief obstacle...to our improvement in the moral or metaphysical sciences is the obscurity of the ideas, and ambiguity of the terms" (EHU, 61), Hume argued that conventional definitions -- defining terms in terms of other terms -- replicate philosophical confusions by substituting synonyms for the original and thus never break out of a narrow "definitional circle." Determining the cognitive content of an idea or term requires something else.

Hume supplied what was required with his account of definition, which offers a simple series of tests to determine cognitive content. First, find the idea to which a term is annexed. If none can be found, then the term has no content, however prominently it may figure in philosophy or theology. If the idea is complex, break it up into the simple ideas of which it is composed. Then trace the simple ideas back to their original impressions: "These impressions are all strong and sensible. They admit not of ambiguity. They are not only placed in a full light themselves, but may throw light on their correspondent ideas, which lie in obscurity" (EHU, 62).

If the process fails at any point, the idea in question lacks cognitive content. When carried out successfully, it yields a full account -- a "just definition" -- of the troublesome idea or term; a Humean definition gives us its exact cognitive content. So, whenever we are suspicious that a "philosophical term is employed without any meaning or idea (as is too frequent), we need but enquire, from what impression is that supposed idea derived? And if it be impossible to assign any, this will serve to confirm our suspicion. By bringing ideas into so clear a light we may reasonably hope to remove all dispute, which may arise, concerning their nature and reality" (EHU, 22).

Hume's account of definition is not only the most distinctive feature of his empiricism, it is also a brilliant strategic device. He regards it as "a new microscope or species of optics, by which, in the moral sciences, the most minute, and most simple ideas may be so enlarged as to fall readily under our apprehension, and be equally known with the grossest and most sensible ideas, that can be the object of our enquiry" (EHU, 62).

Association
The Copy Principle accounts for the origins of our ideas. But our ideas are also regularly connected. As Hume put the point in his "Abstract" of the Treatise, "there is a secret tie or union among particular ideas, which causes the mind to conjoin them more frequently together, and makes the one, upon its appearance, introduce the other" (T, 662).

A science of human nature should account for these connections. Otherwise, we are stuck with an eidetic atomism -- a set of discrete, independent ideas, unified only in that they are the contents of a particular mind. Eidetic atomism thus fails to explain how ideas are "bound together," and its inadequacy in this regard encourages us, as Hume thought it encouraged Locke, to postulate theoretical notions -- power and substance being the most notorious -- to account for the connections we find among our ideas. Eidetic atomism is thus a prime source of the philosophical "hypotheses" Hume aims to eliminate.

The principles required for connecting our ideas aren't theoretical and rational; they are natural operations of the mind, associations we experience in "internal sensation." Hume's introduction of these "principles of association" is the other distinctive feature of his empiricism, so distinctive that in the Abstract he advertises it as his most original contribution: "If any thing can intitle the author to so glorious a name as that of an inventor, 'tis the use he makes of the principle of the association of ideas" (T, 661-662).

Hume locates "three principles of connexion" or association: resemblance, contiguity, and cause and effect. Of the three, causation is the only principle that takes us "beyond the evidence of our memory and senses." It establishes a link or connection between past and present experiences with events that we predict or explain, so that "all reasonings concerning matter of fact seem to be founded on the relation of cause and effect." But causation and the ideas closely related to it also raise serious metaphysical problems: "there are no ideas, which occur in metaphysics, more obscure and uncertain, than those of power, force, energy or necessary connexion" (EHU, 61-62).

Hume wants to "fix, if possible, the precise meaning of these terms, and thereby remove some part of that obscurity, which is so much complained of in this species of philosophy" (EHU, 62). This project provides a crucial experiment for Hume's metaphysical microscope, one designed to prove the worth of his method, to provide a paradigm for investigating problematic philosophical and theological notions, and to supply valuable material for these inquiries.

Causation: The Negative Phase
Hume's strategy dictates that he first show that alternative accounts of our "causal reasonings" are inadequate. This negative project directs his metaphysical microscope toward the intellectualist view that causal connections are made on the basis of the operations of the understanding. Hume proceeds by examining all of the possible ways in which our "causal reasonings" might be based on reason.

Reasoning concerns either relations of ideas or matters of fact. Hume quickly establishes that, whatever assures us that a causal relation obtains, it is not reasoning concerning relations between ideas. Effects are distinct events from their causes: we can always conceive of one such event occurring and the other not. So causal reasoning can't be a priori reasoning.

Causes and effects are discovered, not by reason but through experience, when we find that particular objects are constantly conjoined with one another. We tend to overlook this because most ordinary causal judgments are so familiar; we've made them so many times that our judgment seems immediate. But when we consider the matter, we realize that "an (absolutely) unexperienced reasoner could be no reasoner at all" (EHU, 45n). Even in applied mathematics, where we use abstract reasoning and geometrical methods to apply principles we regard as laws to particular cases in order to derive further principles as consequences of these laws, the discovery of the original law itself was due to experience and observation, not to a priori reasoning.

Even after we have experience of causal connections, our conclusions from those experiences aren't based on any reasoning or on any other process of the understanding. They are based on our past experiences of similar cases, without which we could draw no conclusions at all.

But this leaves us without any link between the past and the future. How can we justify extending our conclusions from past observation and experience to the future? The connection between a proposition that summarizes past experience and one that predicts what will occur at some future time is surely not an intuitive connection; it needs to be established by reasoning or argument. The reasoning involved must either be demonstrative, concerning relations of ideas, or probable, concerning matters of fact and existence.

There is no room for demonstrative reasoning here. We can always conceive of a change in the course of nature. However unlikely it may seem, such a supposition is intelligible and can be distinctly conceived. It therefore implies no contradiction, so it can't be proven false by a priori demonstrative reasoning.

Probable reasoning can't establish the connection, either, since it is based on the relation of cause and effect. What we understand of that relation is based on experience and any inference from experience is based on the supposition that nature is uniform -- that the future will be like the past.

The connection could be established by adding a premise stating that nature is uniform. But how could we justify such a claim? Appeal to experience will either be circular or question-begging. For any such appeal must be founded on some version of the uniformity principle itself -- the very principle we need to justify.

This argument exhausts the ways reason might establish a connection between cause and effect, and so completes the negative phase of Hume's project. The explanatory model of human nature which makes reason prominent and dominant in thought and action is indefensible. Scepticism about it is well-founded: the model must go.

Hume insists that he offers his "sceptical doubts about the operations of the understanding," not as "discouragement, but rather an incitement...to attempt something more full and satisfactory" (EHU, 26). Having cleared a space for his own account, Hume is now ready to do just that.

Causation: The Positive Phase
Hume's negative argument showed that our causal expectations aren't formed on the basis of reason. But we do form them, and "if the mind be not engaged by argument...it must be induced by some other principle of equal weight and authority" (EHU, 41).

This principle can't be some "intricate or profound" metaphysical argument Hume overlooked. For all of us -- ordinary people, infants, even animals -- "improve by experience," forming causal expectations and refining them in the light of experience. Hume's "sceptical solution" limits our inquiries to common life, where no sophisticated metaphysical arguments are available and none are required.

When we examine experience to see how expectations are actually produced, we discover that they arise after we have experienced "the constant conjunction of two objects;" only then do we "expect the one from the appearance of the other." But when "repetition of any particular act or operation produces a propensity to renew the same act or operation...we always say, that this propensity is the effect of Custom" (EHU, 43).

So the process that produces our causal expectations is itself causal. Custom or habit "determines the mind...to suppose the future conformable to the past." But if this background of experienced constant conjunctions was all that was involved, then our "reasonings" would be merely hypothetical. Expecting that fire will warm, however, isn't just conceiving of its warming, it is believing that it will warm.
Belief requires that there also be some fact present to the senses or memory, which gives "strength and solidity to the related idea." In these circumstances, belief is as unavoidable as is the feeling of a passion; it is "a species of natural instinct," "the necessary result of placing the mind" in this situation.

Belief is "a peculiar sentiment, or lively conception produced by habit" that results from the manner in which ideas are conceived, and "in their feeling to the mind." It is "nothing but a more vivid, lively, forcible, firm, steady conception of an object, than what the imagination alone is ever able to attain" (EHU, 49). Belief is thus "more an act of the sensitive, than of the cogitative part of our natures" (T, 183), so that "all probable reasoning is nothing but a species of sensation" (T, 103). This should not be surprising, given that belief is "so essential to the subsistence of all human creatures." "It is more conformable to the ordinary wisdom of nature to secure so necessary an act of the mind, by some instinct or mechanical tendency" than to trust it "to the fallacious deductions of our reason" (EHU, 55). Hume's "sceptical solution" thus gives a descriptive alternative, appropriately "independent of all the laboured deductions of the understanding," to philosophers' attempts to account for our causal "reasonings" by appeal to reason and argument. For the other notions in the definitional circle, "either we have no idea of force or energy, and these words are altogether insignificant, or they can mean nothing but that determination of the thought, acquir'd by habit, to pass from the cause to its usual effect" (T, 657).

Necessary Connection and the Definition of Cause
It remains only for Hume to "confirm and illustrate" his positive account by providing a precise definition of our idea of causation. In doing so, he accounts in his own terms for the necessary connection so many philosophers have taken to be an essential component of the idea of causation.

As we should expect from the preceding discussion, when we examine a single case of two events we regard as causally related, our impressions are only of their conjunction; the single case, taken by itself, yields no notion of their connection. When we go beyond the single case to examine the background of experienced constant conjunctions of similar pairs of events, we find little to add, for "there is nothing in a number of instances, different from every single instance, which is supposed to be exactly similar" (EHU, 75). How can the mere repetition of conjunctions produce a connection?

While there is indeed nothing added to our external senses by this exercise, something does happen: "after a repetition of similar instances, the mind is carried by habit, upon the appearance of one event, to expect its usual attendant, and to believe that it will exist." We feel this transition as an impression of reflection, or internal sensation, and it is this feeling of determination that is "the sentiment or impression from which we form the idea of power or necessary connexion. Nothing farther is in the case" (EHU, 75).

Although the impression of reflection -- the internal sensation -- is the source of our idea of the connection, that experience wouldn't have occurred if we hadn't had the requisite impressions of sensation -- the external impressions -- of the current situation, together with the background of memories of our past impressions of relevant similar instances.

All the impressions involved are relevant to a complete account of the origin of the idea, even though they seem, strictly speaking, to be "drawn from objects foreign to the cause."
Hume sums up all of the relevant impressions in not one but two definitions of cause.

The relation -- or the lack of it -- between these definitions has been a matter of considerable controversy. If we follow his account of definition, however, the first definition, which defines a cause as "an object, followed by another, and where all objects similar to the first are followed by objects similar to the second" (EHU, 76), accounts for all the external impressions involved in the case. His second definition, which defines a cause as "an object followed by another, and whose appearance always conveys the thought to that other" (EHU, 77) captures the internal sensation -- the feeling of determination -- involved. Both are definitions, by Hume's account, but the "just definition" of cause he claims to provide is expressed only by the conjunction of the two: only together do the definitions capture all the relevant impressions involved.

Hume's account of causation provides a paradigm of how philosophy, as he conceives it, should be done. He goes on to apply his method to other thorny traditional problems of philosophy and theology: liberty and necessity, miracles, design. In each case, the moral is that a priori reasoning and argument gets us nowhere: "it is only experience which teaches us the nature and bounds of cause and effect, and enables us to infer the existence of one object from that of another. Such is the foundation of moral reasoning, which forms the greater part of human knowledge, and is the source of all human action and behaviour" (EHU, 164). Since we all have limited experience, our conclusions should always be tentative, modest, reserved, cautious. This conservative, fallibilist position, which Hume calls mitigated scepticism, is the proper epistemic attitude for anyone "sensible of the strange infirmities of human understanding" (EHU, 161).

Moral Philosophy
The cautious attitude Hume recommends is noticeably absent in moral philosophy, where "systems and hypotheses" have also "perverted our natural understanding," the most prominent being the views of the moral rationalists -- Samuel Clarke, Locke, and William Wollaston, the theories of "the selfish schools" -- Hobbes and Mandeville -- and the pernicious theological ethics of "the schools," whose promotion of the dismal "monkish virtues" frame a catalogue of virtues diametrically opposed to Hume's. Although he offers arguments against the "systems" he opposes, Hume thinks the strongest case against them is to be made descriptively: all these theories offer accounts of human nature that experience and observation prove false.

Against the moral rationalists -- the intellectualists of moral philosophy -- who hold that moral judgments are based on reason, Hume maintains that it is difficult even to make their hypothesis intelligible (T, 455-470; EPM, Appendix I). Reason, Hume argues, judges either of matters of fact or of relations. Morality never consists in any single matter of fact that could be immediately perceived, intuited, or grasped by reason alone; morality for rationalists must therefore involve the perception of relations. But inanimate objects and animals can bear the same relations to one another that humans can, though we don't draw the same moral conclusions from determining that objects or animals are in a given relation as we do when humans are in that same relation. Distinguishing these cases requires more than reason alone can provide. Even if we could determine an appropriate subject-matter for the moral rationalist, it would still be the case that, after determining that a matter of fact or a relation obtains, the understanding has no more room to operate, so the praise or blame that follows can't be the work of reason.

Reason, Hume maintains, can at most inform us of the tendencies of actions. It can recommend means for attaining a given end, but it can't recommend ultimate ends. Reason can provide no motive to action, for reason alone is insufficient to produce moral blame or approbation. We need sentiment to give a preference to the useful tendencies of actions.

Finally, the moral rationalists' account of justice fares no better. Justice can't be determined by examining a single case, since the advantage to society of a rule of justice depends on how it works in general under the circumstances in which it is introduced.

Thus the views of the moral rationalists on the role of reason in ethics, even if they can be made coherent, are false.

Hume then turns to the claims of "the selfish schools," that morality is either altogether illusory (Mandeville) or can be reduced to considerations of self-interest (Hobbes). He argues that an accurate description of the social virtues, benevolence and justice, will show that their views are false.

There has been much discussion over the differences between Hume's presentation of these arguments in the Treatise and the second Enquiry. "Sympathy" is the key term in the Treatise, while benevolence does the work in the Enquiry. But this need not reflect any substantial shift in doctrine. If we look closely, we see that benevolence plays much the same functional role in the Enquiry that sympathy plays in the Treatise. Hume sometimes describes benevolence as a manifestation of our "natural" or "social sympathy." In both texts, Hume's central point is that we experience this "feeling for humanity" in ourselves and observe it in others, so "the selfish hypothesis" is "contrary both to common feeling and to our most unprejudiced notions" (EPM, 298).

Borrowing from Butler and Hutcheson, Hume argues that, however prominent considerations of self-interest may be, we do find cases where, when self-interest is not at stake, we respond with benevolence, not indifference. We approve of benevolence in others, even when their benevolence is not, and never will be, directed toward us. We even observe benevolence in animals. Haggling over how much benevolence is found in human nature is pointless; that there is any benevolence at all refutes the selfish hypothesis.

Against Hobbes, Hume argues that our benevolent sentiments can't be reduced to self-interest. It is true that, when we desire the happiness of others, and try to make them happy, we may enjoy doing so. But benevolence is necessary for our self-enjoyment, and although we may act from the combined motives of benevolence and enjoyment, our benevolent sentiments aren't identical with our self-enjoyment.

We approve of benevolence in large part because it is useful. Benevolent acts tend to promote social welfare, and those who are benevolent are motivated to cultivate the other social virtue, justice. But while benevolence is an original principle in human nature, justice is not. Our need for rules of justice isn't universal; it arises only under conditions of relative scarcity, where property must be regulated to preserve order in society.

The need for rules of justice is also a function of a society's size. In very small societies, where the members are more of an extended family, there may be no need for rules of justice, because there is no need for regulating property -- no need, indeed, for our notion of property at all. Only when society becomes extensive enough that it is impossible for everyone in it to be part of one's "narrow circle" does the need for rules of justice arise.

The rules of justice in a given society are "the product of artifice and contrivance." They are constructed by the society to solve the problem of how to regulate property; other rules might do just as well. The real need is for some set of "general inflexible rules...adopted as best to serve public utility" (EPM, 305).

Hobbesians try to reduce justice to self-interest, because everyone recognizes that it is in their interest that there be rules regulating property. But even here, the benefits for each individual result from the whole scheme or system being in place, not from the fact that each just act benefits each individual directly. As with benevolence, Hume argues that we approve of the system itself even where our self-interest isn't at stake. We can see this not only from cases in our own society, but also when we consider societies distant in space and time.

Hume's social virtues are related. Sentiments of benevolence draw us to society, allow us to perceive its advantages, provide a source of approval for just acts, and motivate us to do just acts ourselves. We approve of both virtues because we recognize their role in promoting the happiness and prosperity of society. Their functional roles are, nonetheless, distinct. Hume compares the benefits of benevolence to "a wall, built by many hands, which still rises by every stone that is heaped upon it, and receives increase proportional to the diligence and care of each workman," while the happiness justice produces is like the results of building "a vault, where each individual stone would, of itself, fall to the ground" (EPM, 305).

"Daily observation" confirms that we recognize and approve of the utility of acts of benevolence and justice. While much of the agreeableness of the utility we find in these acts may be due to the fact that they promote our self-interest, it is also true that, in approving of useful acts, we don't restrict ourselves to those that serve our particular interests. Similarly, our private interests often differ from the public interest, but, despite our sentiments in favor of our self-interest, we often also retain our sentiment in favor of the public interest. Where these interests concur, we observe a sensible increase of the sentiment, so it must be the case that the interests of society are not entirely indifferent to us.

With that final nail in Hobbes' coffin, Hume turns to develop his account of the sources of morality. Though we often approve or disapprove of the actions of those remote from us in space and time, it is nonetheless true that, in considering the acts of (say) an Athenian statesman, the good he produced "affects us with a less lively sympathy," even though we judge their "merit to be equally great" as the similar acts of our contemporaries. In such cases our judgment "corrects the inequalities of our internal emotions and perceptions; in like manner, as it preserves us from error, in the several variations of images, presented to our external senses" (EPM, 227). Adjustment and correction is necessary in both cases if we are to think and talk consistently and coherently.

"The intercourse of sentiments" that conversation produces is the vehicle for these adjustments, for it takes us out of our own peculiar positions. We begin to employ general language which, since it is formed for general use, "must be moulded on some general views ... ." In so doing, we take up a "general" or "common point of view," detached from our self-interested perspectives, to form "some general unalterable standard, by which we may approve or disapprove of characters and manners." We begin to "speak another language" -- the language of morals, which "implies some sentiment common to all mankind, which recommends the same object to general approbation, and makes every man, or most men, agree in the same opinion or decision concerning it. It also implies some sentiment, so universal and comprehensive as to extend to all mankind, and render the actions and conduct, even of the persons the most remote, an object of applause or censure, according as they agree or disagree with that rule of right which is established. These two requisite circumstances belong alone to the sentiment of humanity here insisted on" (EPM, 272). It is the extended or extensive sentiment of humanity -- benevolence or sympathy -- that for Hume is ultimately "the foundation of morals."

But even if the social virtues move us from a perspective of self-interest to one more universal and extensive, it might appear that the individual virtues do not. But since these virtues also receive our approbation because of their usefulness, and since "these advantages are enjoyed by the person possessed of the character, it can never be self-love which renders the prospect of them agreeable to us, the spectators, and prompts our esteem and approbation" (EPM, 234).

Just as we make judgments about others, we are aware, from infancy, that others make judgments about us. We desire their approval and modify our behavior in response to their judgments. This love of fame gives rise to the habit of reflectively evaluating our own actions and character traits. We first see ourselves as others see us, but eventually we develop our own standards of evaluation, keeping "alive all the sentiments of right and wrong," which "begats, in noble natures, a certain reverence" for ourselves as well as others, "which is the surest guardian of every virtue" (EPM, 276). The general character of moral language, produced and promoted by our social sympathies, permits us to judge ourselves and others from the general point of view, the proper perspective of morality. For Hume, that is "...the most perfect morality with which we are acquainted" (EPM, 276).

Hume summarizes his account in this definition of virtue, or Personal Merit: "every quality of the mind, which is useful or agreeable to the person himself or to others, communicates a pleasure to the spectator, engages his esteem, and is admitted under the honourable denomination of virtue or merit" (EPM, 277). That is, as observers -- of ourselves as well as others -- to the extent that we regard certain acts as manifestations of certain character traits, we consider the usual tendencies of acts done from those traits, and find them useful or agreeable, to the agent or to others, and approve or disapprove of them accordingly. A striking feature of this definition is its precise parallel to the two definitions of cause that Hume gave as the conclusion of his central argument in the first Enquiry. Both definitions pick out features of events, and both record a spectator's reaction or response to those events.

Politics, Criticism, History, and Religion
Hume's "Advertisement" for the first two books of the Treatise promised subsequent works on morals, politics and criticism, but his Political Discourses, "Of Tragedy," and "Of the Standard of Taste" are our only hints as to what he might have said about those topics.

Hume's political essays range widely, covering not only the constitutional issues one might expect, but also venturing into what we now call economics, dealing with issues of commerce, luxury, and their implications for society. His treatments of these scattered topics exhibit a unity of purpose and method that makes the essays much more than the sum of their parts, and links them, not only with his more narrowly philosophical concerns, but also with his earlier moral and literary essays.

Adopting a causal, descriptive approach to the problems he discusses, Hume stresses that current events and concerns are best understood by tracing them historically to their origins. This approach contrasts sharply with contemporary discussions, which treated these events as the products of chance, or -- worse -- of providence. Hume substitutes a concern for the "moral causes" -- the human choices and actions -- of the events, conditions, or institutions he considers. This thoroughly secular approach is accentuated by his willingness to point out the bad effects of superstition and enthusiasm on society, government, and political and social life.

"Of the Standard of Taste" is a rich contribution to the then-emerging discipline of what we now call aesthetics. This complex essay contains a lucid statement of Hume's views on what constitutes "just criticism," but it is not just about criticism, as some readers are beginning to realize. Though Hume's account of aesthetic judgment precisely parallels his account of causal and moral judgment, the essay also contains a discussion of how a naturalistic theory might deal with questions of normativity, and so is important, not just as a significant contribution to Hume's overall view, but also for its immediate relevance for problems in contemporary empirical naturalism.

Hume's History of England, published in six volumes over as many years in the 1750s, recalls his characterization, in the first Enquiry, of history as "so many collections of experiments." Hume not surprisingly rejects the theoretical commitments of both Tory and Whig accounts of British history, and offers what he believes is an impartial account that looks at political institutions as historical developments responsive to Britons' experience of changing conditions, evaluating political decisions in the contexts in which they were made, instead of second-guessing them in the light of subsequent developments.

The Natural History of Religion is also a history in a sense, though it has been described as "philosophical" or "conjectural" history. It is an account of the origins and development of religious beliefs, with the thinly-disguised agenda of making clear not only the nonrational origins of religion, but also of exposing and describing the pathology of its current forms. Religion began in the postulation, by primitive peoples, of "invisible intelligences" to account for frightening, uncontrollable natural phenomena, such as disease and earthquakes. In its original forms, it was polytheistic, which Hume regards as relatively harmless because of its tolerance of diversity. But polytheism eventually gives way to monotheism, when the followers of one deity hold sway over the others. Monotheism is dogmatic and intolerant; worse, it gives rise to theological systems which spread absurdity and intolerance, but which use reason to corrupt philosophical thought. But since religion is not universal in the way that our nonrational beliefs in causation or physical objects are, perhaps it can eventually be dislodged from human thinking altogether.

Hume's Natural History cemented his reputation as a religious sceptic and an atheist, even before its publication. Prompted by his own prudence, as well as the pleas of his friends, he resisted publishing the Dialogues concerning Natural Religion, which he had worked on since the early 1750s, though he continued revising the manuscript until his death. An expansion and dramatic revision of the argument previewed in Section XI of the first Enquiry, the Dialogues are so riddled with irony that controversy still rages as to what character, if any, speaks for Hume. But his devastating critique of the argument from design leaves no doubt that -- scholarly details about its enigmatic final section aside -- the conclusions philosophers and theologians have drawn from that argument go far beyond any evidence the argument itself provides.

A fitting conclusion to a philosophical life, the posthumously published Dialogues would alone insure the philosophical and literary immortality of their author. In this magnificent work, Hume demonstrates his mastery of the dialogue form, while producing the preeminent work in the philosophy of religion.