Background
Jan Cornets De Groot was born on March 8, 1554, in Delft, Netherlands. He was the son of Hugo Cornelisz and of Elselinge Van Heemskerck.
De Groot entered the University of Leiden on February 5, 1575.
De Groot entered the University of Leiden on February 5, 1575.
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1607
musician politician Patrician poet
Jan Cornets De Groot was born on March 8, 1554, in Delft, Netherlands. He was the son of Hugo Cornelisz and of Elselinge Van Heemskerck.
De Groot (or perhaps a namesake) entered the University of Leiden on February 5, 1575, its opening day. He was awarded the doctorate of law in 1596.
De Groot was a master of liberal arts and philosophy at Douai. Belonging to the Delft patriciate, he was a councillor, and from 1591 to 1595 was one of the mayors. From 1594 to 1617 he was a curator of the University of Leiden. After 1617 he served as adviser to the Count of Hohenlohe.
De Groot is best known through the experiment he performed with Simon Stevin, in which they proved that lead bodies of different weights falling on a board traverse the same distance in the same time. The anti-Aristotelian experiment, published by Stevin in his Walerwicht (1586), anticipated Galileo’s famous, but apocryphal, experiment at the Leaning Tower of Pisa. De Groot also befriended Ludolph Van Ceulen, on whose behalf he translated Archimedes’ Measurement of the Circle from the Greek into Dutch and who submitted to him his approximation of it to 20 decimal places (1586).
Simon Stevin, with whom De Groot collaborated in the construction of windmills, praised him as a man well versed in the whole of philosophy, mentioning Euclid, Alhazen (Ibn al-Haylham), Witelo, music, and poetry.
Van Roomen, in his Ideae mathematicae (1593), praises De Groot as one of the better mathematicians of his time.
In 1582 De Groot married Alida Borren, from Overschie. One of their five children was the jurist known as Hugo Grotius.
Simon Stevin, sometimes called Stevinus, was a Dutch-Flemish mathematician, physicist and military engineer. He was active in a great many areas of science and engineering, both theoretical and practical.
Ludolph van Ceulen was a German-Dutch mathematician from Hildesheim.
