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16 Oct

The discovery of quaternions

If I may be allowed to speak of myself in connexion with the subject, I might do so in a way which would bring you in, by referring to an ante-quaternionic time, when you were a mere child […] Every morning in the early part of the above-cited month [ October, 1843], on my coming down to breakfast, your (then) little brother William Edwin, and yourself, used to ask me, “Well, Papa, can you multiply triplets”? Whereto I was always obliged to reply, with a sad shake of the head: “No, I can only add and subtract them.”


But on the 16th day of the same month – which happened to be a Monday, and a Council day of the Royal Irish Academy – I was walking in to attend and preside, and your mother was walking with me, along the Royal Canal, to which she had perhaps driven; and although she talked with me now and then, yet an under-current of thought was going on in my mind, which gave at last a result, whereof it is not too much to say that I felt at once the importance. An electric circuit seemed to close; and a spark flashed forth, the herald (as I foresaw, immediately) of many long years to come of definitely directed thought and work, by myself if spared, and at all events on the part of others, if I should even be allowed to live long enough distinctly to communicate the discovery. Nor could I resist the impulse – unphilosophical as it may have been – to cut with a knife on a stone of Brougham Bridge, as we passed it, the fundamental formula with the symbols, ijk; namely,
i2 = j2 = k2 = ijk = -1
which contains the Solution of the Problem, but of course, as an inscription, has long since mouldered away.

Letter dated August 5, 1865 from Sir W. R. Hamilton to Rev. Archibald H. Hamilton.

The classic account of the discover of quaternions. Hamilton also notes in this letter that the Council Books of the Academy record that he had obtained leave to read a paper on quaternions, which reading took place on the 13th November 1843.

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22 May

Lyric Feature: A Radical Life

A Radical Life from Lyric Feature on RTE Lyric FM

A documentary, presented by Susan Manly, on the life and work of Maria Edgeworth made for the 170th anniversary of her death . For more on the documentary and Maria Edgeworth see this article from RTE.

07 Apr

The Triumfeminate and other Dublin Women: Swift’s “Female Senate”

Delville, home of the Delanys.

This post originally appeared on my personal blog. However at the recent conference on Irish Philosophy in the Age of Berkeley, Christine Gerrard gave a fascinating presentation on What the Dublin Women of the ‘Triumfeminate’ did with John Locke”. I have therefore moved this post here to serve as an introduction to these women.


In 1752 John Boyle (5th earl of Cork and Orrery), erstwhile friend of Jonathan Swift, wrote in his life of the Dean, “You see the command which Swift had over all his females, and you would have smiled to have found his house a constant seraglio of very virtuous women, who attended him from morning til night”. Boyle blamed Swift’s women for Swift publishing papers he would have been wiser to withhold, since “he communicated every composition as soon as finished, to his female senate.”

Patrick Delany, who had been close friends with Swift since meeting him in 1718, wasted no time in defending the reputation of Swift and his friends in Observations Upon Lord Orrery’s Remarks on the Life and Writings of Dr. Jonathan Swift. As well as giving explanations of Swift’s relationships with Esther Johnson (‘Stella’) and Esther Vanhomrigh (‘Vanessa’), he insisted that women almost never visited the Dean’s house, and then only by invitation. Delany had every opportunity of knowing this: “[Delany’s] house at Glasnevin was the scene of the weekly meetings at which Swift and his circle would read poems to each other and submit them for correction” (Andrew Carpenter, 2004). The house, Delville, has since been demolished but stood on the site of the present Bon Secours Hospital, Dublin.

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22 Mar

Distillations: The Almost Forgotten Story of Katherine Jones, Lady Ranelagh

In this episode of Distillations, the creator and host of Babes of Science, Poncie Rutsch, interviews Michelle DiMeo, an expert on Lady Ranelagh who is currently writing a book on Ranelagh’s life.

The page for the podcast (including a transcript) is here.

17 Mar

Hail Glorious St Patrick – a history of Irish Nationalism

At some point today somewhere on Irish radio, “Hail Glorious St Patrick” will be played. A traditional staple for St Patrick’s day written by a woman, Sr Agnes, this hymn not only praises Patrick and asks for his help for the “poor children” of Ireland, but also praises Ireland itself. Written in the early 19th century, it closes with the assertion that “And our hearts shall yet burn, wherever we roam, For God and Saint Patrick, and our native home.”1

The interaction between nationalism, patriotism and love of country is a complex one. They are not synonymous.

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04 Mar

The Forum for Philosophy: the Irish Enlightenment

The Forum for Philosophy: The Irish Enlightenment (4 March 2019)

On 4th March 2019, the Forum for Philosophy hosted a discussion on the Irish Enlightenment at the LSE. Contributors were Ian McBride (Oxford),
Katherine O’Donnell  (UCD) and Tom Stoneham (University of York). The chair was Clare Moriarty (Forum for Philosophy and UCD).

This interesting discussion is an excellent introduction to the subject of the Irish Enlightenment. The podcast website is here.

30 Jan

Words of Wisdom: the life and work of J. O. Wisdom

OTHERWISE, adj. Knowing the difference between two philosophers with identical interests and the same name, hence otherwisdom, n.

(Indy obit J. O. WISDOM: ‘To the confusion of some
he shared both interests and apposite surname
with cousin Cambridge prof J. A. T. D. Wisdom’)

David Papineau, Twitter.

It can be difficult to distinguish Wisdom. John Oulton Wisdom who was born in Dublin on the 29 December 1908 is often confused with his cousin, also John Wisdom (Arthur John Terence Dibben Wisdom), also a philosopher and who also brought together psychoanalysis and philosophy.

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12 Jan

Edmund Burke and the Fight against Injustice

Edmund Burke and the French Revolution

Lecture given as part of the course “Ireland in Rebellion: 1782-1916” delivered by Prof. Patrick Geoghegan, Department of History, Trinity College Dublin. (11 mins)

29 Dec

Dissolving Philosophy


It is a curious but indisputable fact that every philosophical baby born alive is either a little positivist or a little Hegelian. […]

Professor J. O. Wisdom of York University, Toronto, once observed that he knew people who thought there was no philosophy after Hegel, and others who thought there was none before Wittgenstein, and that he was prepared to contemplate the possibility that both were right.


Ernest Gellner (1987) “Positivism against Hegelianism” in Relativism and the Social Sciences,  Cambridge University Press. Quote on p. 4.

Wisdom was qualified to comment, as someone who studied both, even if his conclusion is cursing both houses! Wisdom was born 110 years ago, on this day.

13 Dec

Cooke against the radicals

Statue of Henry Cooke against bare tree branches

The statue of Henry Cooke (who died on 13th December 1868) stands in Belfast with its back to the “Inst”, the Royal Belfast Academical Institution. Its pose can be seen as a symbol of his determined conflict with the liberal (and, he feared, religiously unorthodox) school [1]. 

A non-denominational establishment founded in 1810 by William Drennan, the Belfast Academical Institution served as both a school and a university. Cooke alleged it was a “seminary of Arianism”, due to the presence of prominent anti-Trinitarians and Unitarians such as William Bruce Jr (chair of Latin, Greek, and Hebrew, nephew of William Bruce the printer) and Henry Montgomery (chair of English) [2]

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