Thomas Fuller (sketch)
*This date in 1710 is celebrated as the birth date of Thomas Fuller, a Black African slave and mathematician.
He was born between present-day Liberia and Benin. He was one of the millions of Black Africans kidnapped to America as a slave at 14 during the Middle Passage. He was the property of Mrs. Elizabeth Cox of Alexandria. When Fuller arrived in 1724, in Virginia, he had already developed his calculation abilities. His learning included number words, a numeration system of arithmetical operations, riddles, and mathematical games.
The evidence of this comes from the sparse evidence of John Bardot's 1732 account of the abilities of the people of Fida (on the coast of Benin); Bardot’s account stated: “The Fidasians are expert in keeping their accounts, that they easily reckon as exact, and as quick by memory, as we can do with pen and ink, though the sum amount to never so many thousands: which very much facilities the trade the Europeans have with them.”
Fuller was a prodigy. Though he could never read or write, he had perfectly acquired the skill of details. He could multiply seven into itself, that product by seven, and the products, so produced, by seven, for seven times. He could give the number of months, days, weeks, hours, minutes, and seconds in any period, including all leap years in the question in his calculation. He would give the number of poles, yards, feet, inches, and barleycorns in any distance, say the diameter of the earth's orbit. In every calculation, he would produce the true answer in less time than ninety-nine men out of a hundred would calculate on paper.
When Fuller was about seventy years old, 'two gentlemen, natives of Pennsylvania, viz., William Hartshorne and Samuel Coates, men of probity and respectable characters having heard, in traveling through the neighborhood in which the slave lived, of his extraordinary powers in arithmetic, sent for him and had their curiosity sufficiently gratified by the answers which he gave to the following questions:
First, When asked how many seconds there were in a year and a half, he answered in about two minutes, 47,304,000. Second: When asked how many seconds a man has lived who is 70 years, 17 days, and 12 hours old, he answered in a minute and a half 2,210,500,800. One of the gentlemen who employed himself with his pen in making these calculations told him he was wrong, and the sum was not so great as he had said - upon which the old man hastily replied: stop, master, you forget the leap year. On adding the number of seconds in the leap years, the amount of the whole in both their sums agreed exactly.
Another question was asked and satisfactorily answered. Before two other gentlemen, he gave the amount of nine figures multiplied by nine. ...In 1790, he died at the age of 80 years, having never learned to read or write despite his extraordinary calculation power. It would be interesting to search for elements of the rich traditional African mathematical education Thomas Fuller had passed through before being sold as a slave to America.
