Professor 'John Playfair'
FRSE (
March 10,
1748 –
July 20,
1819) was a
Scottish scientist.
Playfair was professor of
mathematics and later professor of
natural philosophy at the
University of Edinburgh. He is perhaps best known for his book ''
Illustrations of the Huttonian Theory of the Earth'' (
1802), which was a summary of the work of
James Hutton. It was through this that Hutton's principle of
uniformitarianism, later taken up by
Charles Lyell, first reached a wide audience.
In
1795 Playfair created an alternative formulation of
Euclid's parallel postulate called
Playfair's axiom.
Early life
Born at
Benvie,
Angus, Scotland, where his father was
parish minister, he was educated at home until the age of fourteen, when he entered the
University of St Andrews. In
1766, when only eighteen, he was candidate for the chair of mathematics in
Marischal College,
Aberdeen, and, although he was unsuccessful, his claims were admitted to be high.
Six years later he made application for the chair of natural philosophy in his own university, but again without success, and in
1773 he was offered and accepted the
benefice of the united
parishes of
Liff and Benvie, vacant by the death of his father. He continued, however, to carry on his mathematical and physical studies, and in
1782 he resigned his charge in order to become the tutor of
Ferguson of Raith. By this arrangement he was able to be frequently in
Edinburgh and to cultivate the
literary and scientific society for which it was at that time specially distinguished. In particular, he attended the natural history course of
John Walker. Through
Nevil Maskelyne, whose acquaintance he had first made in the course of the celebrated
Schiehallion experiments in
1774, he also gained access to the scientific circles of
London. In
1785 when
Dugald Stewart succeeded Ferguson in the Edinburgh chair of
moral philosophy, Playfair succeeded the former in that of mathematics.
Mature work
In
1802, he published his celebrated volume entitled ''Illustrations of the Huttonian Theory of the Earth.'' The influence exerted by
James Hutton on the development of
geology is thought to be largely due to its publication. In
1805 he exchanged the chair of mathematics for that of natural philosophy in succession to
John Robison, whom also he succeeded as
general secretary to the
Royal Society of Edinburgh. He took a prominent part, on the
liberal side, in the
ecclesiastical controversy that arose in connexion with Sir
John Leslie's appointment to the post he had vacated, and published a
satirical Letter (
1806).
Playfair was an opponent of
Gottfried Leibniz's ''
vis viva'' principle, an early version of the
conservation of energy. In
1808, he launched an attack
[1] on
John Smeaton and
William Hyde Wollaston's work championing the theory.
He died in Edinburgh.
Family
John's brothers were architect
James Playfair and engineer
William Playfair.
[2]
Honours
★
Fellow of the Royal Society of Edinburgh
★
Fellow of the Royal Society of London,
1807
★
Craters on
Mars and the
Moon were named in his honor.
Notes
1. ''Edinburgh Review'', '12', 1808, 120–130
2. ''Biographical Dictionary of Eminent Scotsmen'' (1856), reproduced in ''Significant Scots''
Critical bibliography
A collected edition of Playfair's works, with a memoir by James G. Playfair, appeared at Edinburgh in 4 vols. 8vo.
His writings include a number of essays contributed to the ''
Edinburgh Review'' from
1804 onwards, various papers in the Phil. Trans. (including his earliest publication, " On the Arithmetic of Impossible Quantities,"
1779, and an " Account of the Lithological Survey of Schehallion,"
1811) and in the ''
Transactions of the Royal Society of Edinburgh'' (" On the Causes which affect the Accuracy of Barometrical Measurements," &c.), also the articles "Aepinus" and "Physical Astronomy," and a "Dissertation on the Progress of Mathematical and Physical Science since the Revival of Learning in Europe," in the
Encyclopædia Britannica (Supplement to fourth, fifth and sixth editions).
His ''
Elements of Geometry'' first appeared in
1795 and have passed through many editions; his ''
Outlines of Natural Philosophy'' (2 vols., 1812-1816) consist of the propositions and
formulae which were the basis of his class lectures. Playfair's contributions to
pure mathematics were not considerable, his paper "On the Arithmetic of Impossible Quantities," that " On the Causes which affect the Accuracy of Barometrical Measurements," and his ''
Elements of Geometry'', all already referred to, being the most important. His lives of
Matthew Stewart,
Hutton,
Robison, many of his
reviews, and above all his "
Dissertation" are of the utmost value.
External links
★
Dictionary of Scientific Biography
★
★
Significant Scots: John Playfair
★
National Portrait Gallery
References
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