"The transition from integrable to non integrable systems is quiet interesting to observe."
Ivar I. Ekeland is a French mathematician of Norwegian descent. Ekeland has written influential monographs and textbooks on nonlinear functional analysis, the calculus of variations, and mathematical economics, as well as popular books on mathematics, which have been published in French, English, and other languages. Ekeland is known as the author of Ekeland's variational principle and for his use
"It is a testimony to the power of education that classical mechanics could operate for so long under a mistaken conception. Teaching and research concentrated on integrable systems, each feeding the other, until in the end we had no longer the tools nor the interest for studying nonintegrable systems."
"We do not discover mathematical truths; we remember them from our passages through this world outside our own."
"Many great failures and many great successes are due to chance and not to human folly or ingenuity."
"Chaos cuts with two edges. We have seen how it is impossible to retrieve past history from current observations. We will now show that it is impossible to predict future states from the current observations."
"So every possible reality, once God gives it existence, will reveal its own identity. Its life will unfold slowly, whereas God encompasses it at a single glance."
"Nowadays, however, we are much more aware of the fact that the best proof in the world is worth no more than its premises: every scientific theory is transitory and provisional, in wait for a better one, and accepted only as long as the experimental results conform to its predictions."