The son of a Scottish minister, I went to the University of St. Andrews to become a minister as well but showed unusual talent in mathematics.
When my father died, I assumed his position in order to support the rest of the family....but left the church 10 years later to pursue being a professor.
In 1795, I published an equivalent to Euclid's parallel postulate that now bear's my name...even though I gave full credit to William Ludlam for its creation.
In addition to my Elements of Geometry, I am best known for my embellishments of my friend James Hutton's works on geology.
Finally, at the request of editors of Encyclopaedia Britannica in 1816, I wrote an extensive essay on the history of mathematics and physical science.
John Playfair (1748 - 1819)