(b. Glasgow, Scotland, 8 March 1788; d. Edinburgh, Scotland, 6 May 1856)
Hamilton’s father, William Hamilton, professor of astronomy at the University of Glasgow, died in 1790, leaving William to be raised by his mother, Elizabeth Hamilton. After receiving a degree from the University of Edinburgh in 1807, Hamilton went to Balliol College. Oxford, with a Snell Exhibition. He quickly acquired the reputation of being the most learned authority in Oxford on Aristotle, and the list of books that he submitted for his final examination in 1810 was unprecedented. He did not, however, receive a fellowship, primarily because of the unpopularity of Scots at Oxford. He returned therefore to Edinburgh to study and there became an advocate in 1813. Because he had little interest in his career in the law, he applied in 1821 for the chair of moral philosophy at Edinburgh vacated by the death of Thomas Brown. Hamilton was a Whig, and the Tory town council therefore chose his opponent, John Wilson. When in 1829 Macvey Napier became the editor of the Edinburgh Review, he persuaded Hamilton to write a series of articles for that journal. The articles, which appeared between 1829 and 1836, were the basis of his international reputation, a reputation that forced the town council to elect him in 1836 to the chair in logic and metaphysics, which he held until his death.
Hamilton’s three most important articles for the Edinburgh Review were those on Cousin (1829), on perception (1830), and on logic (1833). In the first two, he revealed his unique philosophical position, a combination of the Kantian view that there is a limitation on all knowledge and the Scottish view that man has, in perception, a direct acquaintance with the external world.
The first paper deals with the possibility of human knowledge of the absolute. In it Hamilton argued against Cousin’s view that man has immediate knowledge of the absolute and against Schelling’s view that man can know the absolute by becoming identical with it. Hamilton tried to show that neither of these views is coherent and that there is something incoherent about the very notion of thought about the absolute. Hamilton’s own position was close to Kant’s, but he wanted to go further than Kant and say that the mind cannot use the absolute even as a regulative idea.
The second article is a defense of Reid’s view, that the direct object of perception is external, against the attacks of Brown. Hamilton had little trouble in showing that Brown neither understood Reid’s position nor could offer arguments that disproved either Reid’s position or the position mistakenly attributed to him by Brown. Hamilton did, however, agree with Brown’s claim that Reid was mistaken when he identified the direct object of acts of memory with some previously existing external object.
These metaphysical positions were developed further during the twenty years that Hamilton was professor at Edinburgh. Many of his mature opinions, as expressed in the appendixes to his edition of Reid’s major works and to his own published lectures, modify what he wrote in these two articles; but he never really gave up these basic positions, which were extremely influential during his lifetime and still have some interest today. They are, however, far less important for the history of thought in general and for the history of science in particular than his work in logic.
Hamilton was one of the first in that series of British logicians—a series that included George Boole, Augustus De Morgan, and John Venn—who radically transformed logic and created the algebra of logic and mathematical logic. To be sure, Hamilton only helped begin this development, and given his dislike of mathematics, he probably would not have been very happy with its conclusion. Nevertheless, his place in it must be recognized.
The traditional, Aristotelian analysis of reasoning allowed for only four types of simple categorical propositions:
(A) All A are B.
(E) No A are B.
(I) Some A are B.
(O) Some A are not B.
Hamilton’s first important insight was that logic would be more comprehensive and much simpler if it allowed for additional types of simple categorical propositions. In particular, Hamilton suggested that one treat the signs of quantity (“all,” “some,” “no”) in the traditional propositions as modifiers of the subject term A and that one introduce additional signs of quantity as modifiers of the predicate term B. Hamilton called this innovation the quantification of the predicate. Other logicians before Hamilton had made the same suggestion, but Hamilton was the first to explore the implications of quantifying the predicate, of admitting eight simple categorical propositions:
(1) All A are all B.
(2) All A are some B (traditional A).
(3) Some A are all B.
(4) Some A are some B (traditional I).
(5) Any A is not any B (traditional E).
(6) Any A is not some B.
(7) Some A are not any B (traditional O).
(8) Some A are not some B.
The first important inference that Hamilton drew from this modification had to do with the analysis of simple categorical propositions. There were, according to the traditional, Aristotelian logic, two ways of analyzing a simple categorical proposition such as “All A are B”: extensively, that is, as asserting that the extension of the term A is contained within the extension of the term B; or comprehensively, that is, as asserting that the comprehension of the term B is contained within the comprehension of the term A. In either case, the proposition expresses a whole-part relation. But the new Hamiltonian modification, because it distinguished (1) from (2), (3) from (4), (5) from (6), and (7) from (8), enables one to adopt a different analysis of these propositions. According to this new analysis, each of these propositions asserts or denies the existence of an identity-relation between the two classes denoted by the quantified terms. Thus, “All A are all B” asserts that the classes A and B are identical, while “Some A are not some B” asserts that there is a subset of the class A which is not identical with any subset of the class B. One result, therefore, of the quantification of the predicate is that simple categorical propositions become identity claims about classes. This is just the analysis of simple categorical propositions that Boole needed and used in formulating the algebra of logic.
Hamilton’s work facilitated a considerably simplified analysis of the validity of reasoning. The traditional, Aristotelian analysis of mediate reasoning, for example, involved many concepts (such as the figure of a syllogism, major and minor terms) that were based on the distinction between the subject of a proposition and its predicate. This subject-predicate distinction had some significance when simple categorical propositions were understood as expressing asymmetrical whole-part relations. But given the new analysis, where these propositions are understood as expressing symmetrical identity relations, there is little point to a distinction between the subject and the predicate of a proposition. Further, if the subject-predicate distinction is dropped, then all of the traditional cumbersome machinery based on it should also be dropped. As a result, the complicated traditional rules for the validity of syllogistic reasoning disappear. One is then left, as Hamilton pointed out in his theory of the unfigured syllogism, with two simple rules for valid syllogisms: If A = B and B = C, then A = C; and If A = B and B ≠ C, then A ≠ C. Similarly, the traditional Aristotelian analysis of immediate reasoning, based upon the complicated distinctions between simple conversion, conversion per accidens, and contraposition, is replaceable by the simple rule that all eight propositions are simply convertible. This rule follows directly from the fact that all eight propositions are concerned with symmetrical identity relations.
New advances in a given science, besides simplifying the treatment of previously solved problems, usually enable one to solve problems that one could not previously handle. Hamilton’s quantification of the predicate is no exception to this rule. The logician could now explain the validity of many inferences that resisted traditional analysis. The simplest example of this is the inference to the identity of classes A and C from premises asserting that they are both identical with some class B. Traditional analysis did not even recognize the existence of propositions asserting that two classes are identical; it could not, therefore, explain the validity of such an inference. Hamiltonian analysis, however, could do so by referring to the first of the two rules for the validity of all mediate reasoning.
Some of Hamilton’s new ideas, such as his classidentity analysis of propositions, were incorporated into Boole’s far more sophisticated system. This contribution to mathematical logic would in itself be sufficient to earn for Hamilton an important place in intellectual history, but his claim to recognition is strengthened by the significance of his innovations to the history of logic. As is well known, Kant and most other important eighteenth-century philosophers thought that nothing of importance had been done in formal logic since the time of Aristotle, primarily because of the completeness and perfection of the Aristotelian system. The only people who saw a future for logic were those who wanted to change logic from a formal analysis of the validity of reasoning to an epistemological and psychological analysis of the conditions for, and limits on, human knowledge. Hamilton, by showing that the Aristotelian analysis could be greatly improved and supplemented, changed the minds of many philosophers, logicians, and mathematicians and helped produce the interest in formal logic that was so necessary for the great advances of the nineteenth century.
Despite its great historical significance, Hamilton’s quantification of the predicate has had little direct influence in more recent times. This is partly due to the fact that both it and the Boolean algebra of logic, which it so greatly influenced, have been superseded by Frege’s far more powerful quantificational analysis—an analysis so different that Hamilton’s theory has no relevance to it. It is, however, also due to a certain internal weakness in Hamilton’s initial quantification of the predicate, which was pointed out by Hamilton’s great adversary, Augustus De Morgan, during their long and acrimonious quarrels.
There really were two quarrels between Hamilton and De Morgan. The first had to do with Hamilton’s charge that De Morgan had plagiarized some of Hamilton’s basic ideas. In 1846 De Morgan sent a draft of one of his most important papers on logic to William Whewell, who was supposed to transmit it to the Cambridge Philosophical Society. De Morgan then received from Hamilton, in the form of a list of requirements for a prize essay set for Hamilton’s students, a brief account of Hamilton’s quantification of the predicate. At about this time, De Morgan asked Whewell to return the draft of his paper and then made some changes in it. Hamilton charged that the alterations were based on his communication to De Morgan. In his reply De Morgan claimed that he made the changes before he received the communication from Hamilton. Although it is not clear as to who was right about the date of the changes, it is clear that De Morgan did not plagiarize Hamilton’s ideas. Even if De Morgan’s ideas were suggested by Hamilton’s communication, they are so different from Hamilton’s that no one could consider them to be a plagiarism.
The second, far more important, quarrel was about the relative merits of their innovations in logic. This arose out of the first, since De Morgan was not content with pointing out the differences between the two systems. He also argued that Hamilton’s innovations, unlike his own, were based on a defective list of basic propositions.
De Morgan first made this claim in an appendix to his book Formal Logic (1847). Although he offered several criticisms of Hamilton’s list of eight basic categorical propositions, there was only one that was really serious—that Hamilton’s first proposition is not a simple categorical proposition because it is equivalent to the joint assertion of the second and third propositions. Thus “All A are some B” and “Some A are all B” can both be true if, and only if, “All A are all B” is also true.
Hamilton was slow in responding to this argument, primarily because he had suffered an attack of paralysis in 1844 that made it very difficult for him to do any work. When, however, in 1852, he published a collection of his articles from the Edinburgh Review, he included in the book an appendix in which he argued that De Morgan’s criticisms were based on a misunderstanding of the eight propositional forms. De Morgan thought that “some” meant “some, possibly all.” If it did, then he would certainly be right in his claim that the first proposition is equivalent to the joint assertion of the second and third propositions. But Hamilton said that he had meant in his forms “some, and not all.” Consequently, the conjunction of “All A are some B” and “Some A are all B” is inconsistent, and neither of these propositions can be true if “All A are all B” is true.
The controversy rested at this point until some years after Hamilton’s death. Then, De Morgan renewed it in a series of letters in Athenaeum (1861–1862) and in his last article on the syllogism, in Transactions of the Cambridge Philosophical Society (1863). De Morgan began his new attack by casting doubt on the claim that Hamilton had meant “some, but not all.” He did this by showing that much of what Hamilton had to say about the validity of particular inferences made sense only if we suppose that he meant “some, perhaps all.” There is little doubt that De Morgan was right about this point. Yet De Morgan now had an even more crushing criticism of Hamilton’s list of simple categorical propositions: Even if one grants, he said, that Hamilton meant “some, but not all,” there is still something wrong with his list. After all, there are five, and only five, relations of the type discussed in categorical propositions that can hold between two classes: (1) the two classes are coextensive, (2) the first class is a proper subset of the second class, (3) the second class is a proper subset of the first class, (4) the two classes have some members in common but each has members that are not members of the other, and (5) the two classes have no members in common. Thus Hamilton’s propositions 6–8 seem to be superfluous.
De Morgan’s final critique clearly showed that Hamilton had not exercised sufficient care in laying the foundations for his new analysis of the validity of reasoning. This was quickly recognized by most logicians; Charles Sanders Peirce, the great American logician, described De Morgan’s 1863 paper as unanswerable. While there is no doubt that De Morgan’s critique helped lessen the eventual influence of Hamilton’s work, it should not prevent the recognition of both the intrinsic merit of Hamilton’s work and its role in the development of mathematical logic in Great Britain during the nineteenth century.
I. Original Works. Hamilton’s main writings are important essays supplementary to The Works of Thomas Reid (Edinburgh, 1846); Discussions on Philosophy and Literature and Education and University Reform (Edinburgh, 1852); Lectures on Metaphysics, H. Mansel and J. Veitch, eds. (Edinburgh, 1859); and Lectures on Logic, H. Mansel and J. Veitch, eds. (Edinburgh, 1861).
II. Secondary Literature. On Hamilton and his work, see T. S. Baynes, An Essay on the New Analytic of Logical Forms (Edinburgh, 1850); S. A. Grave, The Scottish Philosophy of Common Sense (Oxford, 1960); L. Liard, Les logiciens anglais contemporains (Paris, 1890); J. S. Mill, An Examination of Sir William Hamilton’s Philosophy (London, 1889); S. V. Radmussen, The Philosophy of Sir William Hamilton (Copenhagen, 1925); and J. Veitch, Sir William Hamilton (Edinburgh, 1869).
Baruch A. Brody
(b. Scotland, 13 December 1730; d. London, England, 6 April 1803)
William Hamilton is best known for his diplomatic career and perhaps also for his wife Emma’s notorious affair with Horatio Nelson. His scientific reputation rests on his hobbies—the study of volcanism and the collection of antiquities. After extended military duties, he became the envoy of Great Britain at the court of Naples.
In his first four years in Naples, he climbed Vesuvius at least twenty-two times, during which he or Pietro Fabris, an artist he had trained, did numerous sketches of all the stages of the eruptions which they were able to observe. In order to maintain a complete record of volcanic activity around Naples when he could not observe himself, Hamilton employed, about 1791, a Dominican friar named Resina who kept a daily account of the phenomena.
Hamilton’s scientific activity was not limited to the observation of volcanic eruptions but also included the collection of various types of lavas, ashes, and minerals produced by volcanism in the Naples vicinity. He donated this collection to the British Museum in 1767. Hamilton then extended his investigations to Etna and the Lipari Islands and in February 1783 traveled to Calabria to survey the effects of the earthquakes which had just devastated that area.
Elected a fellow of the Royal Society in 1766, Hamilton published the results of his studies on volcanoes in the form of numerous letters in the Philosophical Transactions (1767–1795). In addition, he published several beautifully illustrated volumes, unique by their association of a French and English text.
Hamilton was a famous collector of antiquities, especially of Greek vases. One collection was sold to the British Museum and the other to Thomas Hope. Hamilton said that the study of antiquities had taught him “the perpetual fluctuation of everything and that the present hour was the sweetest in life.” This virtually Epicurean attitude appears in his complaisance toward his wife and Nelson. In 1800 he was recalled to England and although he hinted many times at a separation, the affair continued and both were at his bedside when he died.
Hamilton would have been considered only a collector of antiquities and an educated observer of volcanic eruptions had he not played an important role, probably unknown to him, in the basalt controversy. In 1769 Rudolf Erich Raspe, curator of the Fridericianum Museum and professor at the Collegium Carolinum in Kassel, wrote his paper entitled “Nachricht von einigen niederhessischen Basalten...” (published in 1771), which Goethe considered epochal because it introduced to Germany the volcanic origin of basalt as demonstrated by Desmarest’s discoveries in Auvergne. Raspe, although convinced of the volcanic origin of basalt, had observed in the Habichtswald, near Kassel, prismatic basalt overlain by massive basalt and had interpreted this situation as representing the products of submarine eruptions overlain by those of subaerial eruptions. On the other hand, Desmarest, in Auvergne, had followed the subaerial lava flows from their terminal accumulations of prismatic basalt to the craters of the volcanoes from which they originated. Still Raspe remained unconvinced, considering that the occurrence in Auvergne could be accidental. He therefore wrote to Hamilton, whom he considered the most qualified naturalist on the question of recent prismatic basalt. In his letter, dated 31 October 1769, Raspe wrote in particular: “I would like to know from your Excellency, if you have found among the new lavas of the Vesuvius, anything which confirms the interpretation of Mr. Desmarest; in other words, do any of the cooled lava flows of the Vesuvius display toward their end something similar to prismatic basalt?” Hamilton replied (12 December 1769) that he had never found any kind of columnar or polygonal rock like basalt among the numerous types of lavas of Vesuvius, Sicily, and Ischia.
This statement was understood by Raspe as support for his hypothesis that prismatic basalt was characteristic of submarine eruptions. Subsequently, he further developed his ideas in Beytrag zur allerältesten und natürlichen Historie von Hessen (1774), translated into English during his self-imposed exile in Great Britain (1776), where he had fled to avoid prosecution for embezzlement.
The proof that Raspe thought he had obtained from Hamilton was actually unwarranted. Although Hamilton might have observed among Vesuvian and Sicilian lavas some true basaltic types comparable to those described by Raspe, the phenomenon of prismatic jointing is complex—not as yet fully understood—and certainly cannot be used as a criterion to distinguish between subaerial and submarine lavas.
I. Original Works. A comprehensive and well-annotated bibliography of Hamilton’s writings is in Doria (see below). Among them are Antiquités étrusques, grecques et romaines, tirées du cabinet de M. Hamilton... Collection of Etruscan, Greek and Roman Antiquities..., 4 vols. (Naples, 1766–1767), with intro. by P. F. Hugues d’Hancarville; “Antwort-Schreiben von Herrn W. Hamilton an R. E. Raspe, aus dem französischen,” in Deutsche Schriften der K. Gesellschaft der Wissenschaften zu Göttingen, 1 (1771), 89–93; Observations on Mount Vesuvius, Mount Etna, and Other Volcanos: In a Series of Letters Addressedto the Royal Society... (London, 1772; repr., 1773, 1774); “Voyage au mont Ethna et observations par M. Hamilton,” in J. H. von Riedesel, Voyage en Sicile et dans la Grande Grèce (Lausanne, 1773), translated from English by Villebois; Campi phlegraei. Observations on the Volcanos of the Two Sicilies... Observations sur les volcans des Deux-Siciles (Naples, 1776); Account of the Discoveries at Pompei (London, 1777); Supplement to the Campi phlegraei, Being an Account of the Great Eruption of Mount Vesuvius, in the Month of August 1779... Supplément au Campi phlegraei... (Naples, 1779); Oeuvres complètes de M. le chevalier Hamilton (Paris, 1781), a French trans., with comments by the Abbé Giraud-Soulavie; “An Account of the Earthquakes Which Happened in Italy From February to May 1783,” in Philosophical Transactions of the Royal Society, 63 (1783), 169–208, repr. as An Account of the Earthquakes in Calabria, Sicily, & c. (Colchester, 1783) and translated into French by Lefebvre de Villebrune as Détails historiques des tremblemens de terre arrivés en Italie... (Paris, 1783); Neuere Beobachtungen über die Vulkane Italiens und am Rhein... (Frankfurt-Leipzig, 1784), a partial German trans. of the French ed. of his complete works; Antiquités étrusques, grecques et romaines, 5 vols. (Paris, 1785–1788), with text by Hancarville; and Collection of Engravings From Ancient Vases, Mostly of Pure Greek Workmanship, Discovered... During the Course of the Years 1789 and 1790..., 5 vols. (Naples, 1791–1795), which appeared in French trans. as Recueil de gravures d’après des vases antiques..., 2 vols. (Paris, 1803–1806).
II. Secondary Literature. On Hamilton and his work, see Gino Doria, ed., Campi phlegraei osservazioni sui volcani delle Due Sicilie... (Milan, 1962), with bibliography by Uberto Limentani; B. Fothergill, Sir William Hamilton: Envoy Extraordinary (London, 1969); R. E. Raspe, “Anhang eines Schreibens an den königlichen Grossbrittanischen Gesandten Herrn William Hamilton, zu Neapolis,” in Deutsche Schriften der K. Gesellschaft der Wissenschaften zu Göttingen, 1 (1771), 84–89; “A Letter Containing a Short Account of some Basalt Hills in Hassia,” in Philosophical Transactions of the Royal Society, 41 (1771), read to the society on 8 Feb. 1770; and An Account of some German Volcanoes and Their Productions... (London, 1776); and D. D. Stacton, Sir William, or a Lesson in Love (New York, 1963).
Albert V. Carozzi
December 9, 1836
The abolitionist William Hamilton was born in New York sometime in 1773. He was reputed to be the illegitimate son of the American statesman Alexander Hamilton, the nation's first secretary of the treasury, though evidence for the accuracy of this rumor is lacking. He made a living as a carpenter, but he made his name as a powerful orator working to improve the conditions of African Americans. In 1808 he cofounded and became president of the New York African Society for Mutual Relief, which provided funds for the widows and children of its members.
One of the country's earliest black abolitionists, Hamilton delivered an antislavery speech, An Address to the New York African Society for Mutual Relief, on January 2, 1809. The address was published a week later at his listeners' request. In the speech, Hamilton celebrated the recent ending of the American slave trade and promoted the education of African Americans. He expressed confidence that "soon shall that contumelious assertion of the proud be proved false, to wit, that Africans do not possess minds as ingenious as other men."
In 1820 Hamilton was one of the founding members of the African Methodist Episcopal Zion (AMEZ) Church in New York City. On July 4, 1827, he gave a major oration at the church to commemorate the New York State emancipation statute. While in his earlier speech he insisted on the equality of the races, in this oration he proclaimed the superiority of blacks, noting that "if there is any difference in the species, that difference is in favour of the people of colour." Arguing that no white American could claim superiority to African Americans as long as he continued to hold slaves, Hamilton asked, "Does he act in conformity to true philosophy?"
Having made clear his contempt for the true motives of white men—"authority and gold"—and having accomplished his expressed goal "to unravel this mystery of superiority," Hamilton proceeded to exhort the young men of his audience to further study and education, and to rouse themselves from "frivolity and lethargy." Giving the lie to the supposed lethargy of African Americans, Hamilton was tireless in his endeavors on their behalf. He helped to organize the first annual Convention for the Improvement of Free People of Color held in Philadelphia on September 20, 1830. As president of the fourth annual convention, held in New York in June, 1834, he gave a well-received speech published as Minutes of the Fourth Annual Convention, for the Improvement of the Free People of Color. As a member of the Phoenix and Philomathean societies he worked towards improving the education of African Americans.
Strongly opposed to the American Colonization Society, Hamilton was a staunch supporter of the abolitionist William Lloyd Garrison, whom he knew personally. He publicized Garrison's Liberator, and helped in the publication of Garrison's Thoughts on Colonization. Hamilton died in or near New York City in 1836. His sons, Robert and Thomas, established two newspapers The People's Press and The Anglo-African.
Boardman, Helen M. "First Families of Manhattan." Phylon (Second Quarter 1944): 138–142.
Ottley, Roi, and William J. Weatherby. The Negro in New York. New York: New York Public Library, 1967.
Porter, Dorothy, ed. Early Negro Writing: 1760–1837. Boston: Beacon Press, 1971. Reprint: Baltimore, MD: Black Classic Press, 1994.
Walls, William. The African Methodist Episcopal Zion Church: Reality of the Black Church. Charlotte: A.M.E. Zion Publishing House, 1974.
lydia mcneill (1996)
Hamilton, William Hamilton, 2nd duke of