Silvanus Phillips Thompson (1851 – 1916) was a professor of physics at the City and Guilds Technical College in Finsbury, England. He was elected to the Royal Society in 1891 and was known for his work as an electrical engineer and as an author.

Thompson's most enduring publication is his 1910 text Calculus Made Easy, which teaches the fundamentals of infinitesimal calculus, and is still in print. Thompson also wrote a popular physics text, Elementary Lessons in Electricity and Magnetism, as well as biographies of Lord Kelvin and Michael Faraday.

In 11 February 1876 he heard Sir William Crookes give an evening discourse at the Royal Institution on The Mechanical Action of Light when Crookes demonstrated his light mill or radiometer. Thompson was intrigued and stimulated and developed a major interest in light and optics (his other main interest being electromagnetism). In 1876 he was appointed as a lecturer in Physics at University College, Bristol, and later was made Professor in 1878 at the age of 27.

Silvanus Thompson, at about the age of 25. A major concern of Thompson was the area of technical education and he made a series of continental tours to France, Germany and Switzerland to compare the continental approach to that in the UK. In 1879 he gave a paper at the Royal Society of Arts on Apprenticeship, Scientific and Unscientific in which he detailed the deficiencies in technical education in England.

In the discussion, the opinion was expressed that England was too conservative to make use of trade schools and that continental methods would not be applicable in the UK. Thompson recognised that technical education was the means by which scientific knowledge could be put into action and spent the rest of his life putting his vision into practical realisation.

In 1878 the City and Guilds of London Institute for the Advancement of Technical Education was founded. Finsbury Technical College was a teaching institution created by the City and Guilds Institute and it was as its Principal and Professor of Physics that Thompson was to devote the next 30 years.

Thompson's particular gift was in his ability to communicate difficult scientific concepts in a clear and interesting manner. He attended and lectured at the Royal Institution giving the Christmas lectures in 1896 on Light, Visible and Invisible with an account of Rontgen Light.