George Gabriel Stokes (13 August 1819 – 01 February 1903) was born in Skreen, Ireland and educated at Pembroke College, Cambridge University. He was a mathematician and physicist. Stokes’ theorem in vector calculus (∯ ∇×U⋅da = ∮U⋅ds) is due to him. He also contributed other results to fluid dynamics and optics, including the first use of the Reynolds number for fluid viscosity (Reynolds number Re =uL/ν, Stokes flow: F = 6πμau = γu).
Though he married in St Patrick’s Cathedral at Armagh, Ireland, in the Catholic Archdiocese of Armagh, he was known to be have belonged to an Anglican family. While serving as vice-president of the British and Foreign Bible Society, he was involved in doctrinal debates about missionary societies. He was also the president of the Victoria Institute (created in 1865 to explore the relationship between religion and science) from 1886 to 1903.
His Memoirs included a philosophical interpretation of Darwin’s theory, making an important distinction between a cause of existence and a mode of existence. Letter of Sir George Gabriel Stokes, to Arthur H. Tabrum, 4 January 1901, Cambridgeshire.
“[E]volution is not a cause, but the description of a process … Can we in any way explain the origin of species? Are we to suppose that each species, or what we regard as a species, originated in the fiat of an almighty power? Or are we to suppose that we are to go indefinitely backwards, and affirm that a chain of secondary causation is to be continued indefinitely backwards? … The treatment of evolution as a cause, capable of leading us on indefinitely, tends to shut out the idea of a First Cause; its treatment as a possible mode of sequence, leading us a step or two onwards, still leaves the mind directed towards a First Cause, though ‘Clouds and darkness are round about Him.’ [cf. Psalm 97] … Remember, Evolution does not mean a cause.”
It is generally acknowledged the papers Stokes wrote on mathematical topics were deeply related to his physical experiments. Stokes argued mathematics was and always would be secondary to physical experimentation in terms of developing scientific knowledge. While math could help describe and formalize our observations he claimed it alone could not prove anything about the various phenomena we observe. As part of his experimental drive, Stokes helped to set up the Cavendish laboratory in the mid 1880s. The lab aimed at directing more of Cambridge’s bright young minds to experimental issues in physics rather than solely pure mathematics. The laboratory started in 1884 was first run by J. J. Thomson (who went on to develop a theory of atomic structure with Ernest Rutherford).
Stokes was often considered the authority on questions of optics in particular the functioning of the eye and the refraction of light waves in the eye’s structures. Yet he never ended up writing a final treatise on the subject though his colleagues long expected one from him. His personal friend and lifelong colleague Sir William Thomson or Lord Kelvin lamented that Stokes’s various administrative duties had taken up too much of his time.
In the early 1840s he calculated the maximum height of various massive waves in the ocean; in 1849 he wrote two papers on variable gravitation on the Earth’s surface which is said to have reformed the science of geodesy. While it was known that the force of gravity differed depending on where a person was on Earth, Stokes claimed that this was not dependent upon the interior composition of the Earth which had been assumed to be the case up until then.
He was married to Mary Robinson, the daughter of Dr. Romney Robinson, astronomer of Armagh. They had five children, two of whom died in childhood. He spent his final years living with his daughter Isabella Lucy who wrote a laudatory memoir of her father following his death. Stokes died on 1 February 1903 and was buried four days later in Mill Road cemetery Cambridge.
– Larmor, Joseph, and Sir George Gabriel Stokes. Memoir and Scientific Correspondence of the Late Sir George Gabriel Stokes. (Cambridge, UK: University Press, 1907), 90.
– Josipa Petrunic, The Griffold Lecturers: George Gabriel Stokes, Lucasian Professor of Mathematics, Cambridge