X-Nico

unusual facts about Playfair's axiom


Playfair's axiom

In 1795 John Playfair published a different formulation of Euclid's parallel postulate, which is now called Playfair's axiom; though the axiom bears Playfair's name, he did not create it, but credited others, in particular William Ludlam, with the prior use of it.


2009–10 Calgary Flames season

Playfair gained notoriety late in the season after video of his wild tantrum against referee Jamie Koharski that involved the coach smashing two sticks went viral.

Andrew Wise

As was typical of publishers of his era, he published religious and homiletic works, like The Pathway to Perfection and The Mean of Mourning (both 1596) by Thomas Playfair — though he appears to have operated a rather small-scale business, in comparison with other stationers of his generation.

Arthur Playfair

Playfair married the actress Lena Ashwell OBE in 1896; he began divorce proceedings in 1903 following her adultery with Robert Taber, the former husband of actress Julia Marlowe.

Claud Lovat Fraser

In 1919 he produced the designs for Nigel Playfair's (1874–1934) ground-breaking production of As You Like It in Stratford upon Avon, then in 1920 for Playfair's highly successful London revival of John Gay's The Beggar's Opera.

Donald A. Martin

Among Martin's most notable work are the proofs of analytic determinacy (from the existence of a measurable cardinal), Borel determinacy (from ZFC alone), the proof (with John R. Steel) of projective determinacy (from suitable large cardinal axioms), and his work on Martin's axiom.

Hong Kong sanitary board election, 1915

Bowley was nominated by David Landale and seconded by Henry Pollock, Fitzwilliams by Henry Pollock and H. W. Looker and Goldring by E. J. Grist and H. S. Playfair.

Judy Playfair

Coming from New South Wales, Playfair combined with Janet Steinbeck, Lyn McClements and Lynne Watson to register a silver medal in the 4x100m medley relay, trailing the Americans home by 1.7s.

Mount Pluto

Mount Pluto, Australia, a volcanic cone associated with Mount Hutton and Mount Playfair, in Northern Territory

Percy Bernard, 5th Earl of Bandon

Bandon married Maybel Elizabeth Playfair, the daughter of Raymond Playfair, on 28 February 1933 at Nairobi Cathedral, in Kenya.

Playfair cipher

Advanced thematic cryptic crosswords like The Listener Crossword (published in the Saturday edition of The Times (UK) newspaper) occasionally incorporate Playfair ciphers.

William Playfair

Ian Spence and Howard Wainer in 2001 describe Playfair as "engineer, political economist and scoundrel" while "Eminent Scotsmen" calls him an "ingenious mechanic and miscellaneous writer."

Two decades before Playfair's first achievements, in 1765 Joseph Priestley had created the innovation of the first timeline charts, in which individual bars were used to visualize the life span of a person, and the whole can be used to compare the life spans of multiple persons.


see also