Leonhard Euler

Leonhard Euler (April 15, 1707–September 18, 1783) was a Swiss mathematician and physicist. He is considered to be one of the greatest mathematicians who ever lived. Leonhard Euler was the first to use the term "function" (defined by Leibniz in 1694) to describe an expression involving various arguments; i.e., y = F(x). He is credited with being one of the first to apply calculus to physics.

Biography

Leonhard Euler was born in Basel, Switzerland, the son of Paul Euler, a Lutheran minister. Although in his childhood he exhibited great mathematical talents, his father wanted him to study theology and become a minister. In 1720 Euler began his studies at the University of Basel. There Euler met Daniel and Nikolaus Bernoulli, who noticed Euler's skills in mathematics. Paul Euler had attended Jakob Bernoulli's mathematical lectures and respected his family. When Daniel and Nikolaus Bernoulli asked him to allow his son to study mathematics he finally agreed and Euler began to study mathematics.

Related Topics:
Basel - Switzerland - Lutheran - Minister - Theology - 1720 - University of Basel - Daniel - Nikolaus Bernoulli - Jakob Bernoulli

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In 1727 Euler was called to St. Petersburg by Catherine I of Russia and became professor of physics in 1730, with an additional mathematics appointment in 1733. Euler was the first to publish a systematic introduction to mechanics in 1736: Mechanica sive motus scientia analytice exposita ("Mechanics or motion explained with analytical science"—that is, calculus). In 1735 he lost much of his vision in the right eye due to excessive observation of the sun.

Related Topics:
1727 - Catherine I of Russia - Physics - 1730 - 1733 - Mechanics - 1736 - 1735 - Sun

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In 1733 he married Katharina Gsell, the daughter of the director of the academy of arts. They had thirteen children, of whom only three sons and two daughters survived. The descendants of these children, however, were in high positions in Russia in the 19th century.

Related Topics:
1733 - 19th century

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In the year 1741 Euler became director of the mathematical class at the Prussian Academy of Sciences in Berlin. His time in Berlin was very productive; however, he did not have an easy position due to a lack of the king's favor. Therefore he returned to St. Petersburg in 1766, ruled by Catherine the Great at that time, and he remained there for the rest of his life.

Related Topics:
1741 - Prussian Academy of Sciences - Berlin - 1766 - Catherine the Great

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Euler continued to be very productive, despite a complete loss of vision, due to his extraordinary powers of memory and mental calculation. It is reported that once he let his assistant calculate a series to 17 summands and noticed that his own result and the assistant's result differed in the 50th digit—a recalculation showed that Euler was right.

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It has been calculated that it would take eight-hours work per day for 50 years to copy all his works by hand. It was not till the year 1910 that a collection of his complete works was published; it took about 70 volumes. It is reported by Legendre that often he would write down a complete mathematical proof between the first and the second call for supper.

Related Topics:
1910 - Legendre

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Euler was a deeply religious Calvinist throughout his life. However, a widely told anecdote that says that Euler challenged Denis Diderot at the court of Catherine the Great with "Sir, (a+b)n/n = x; hence God exists, reply!" is false.

Related Topics:
Calvinist - Anecdote - Denis Diderot

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When Euler died, the mathematician and philosopher Marquis de Condorcet commented, "...et il cessa de calculer et de vivre" (and he ceased to calculate and to live).

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