Abstract

Euler's contributions to differential equations are so comprehensive and rigorous that any contemporary textbook on the subject can be regarded as a copy of Euler's Institutionum Calculi Integralis. Of course, Euler's work is an improvement of that of Leibniz, the Bernoullis, Newton and so many others before them, but still it's so outstanding that will be used in this paper as a reference to account for every previous or subsequent development in ODEs. Maybe Euler did not discovered differential equations, but he did not discovered less differential equations than Newton and Leibniz had discovered differential calculus a few decades before.