An announcement of [Christopher] Zeeman's lecture at Northwestern University in the spring of 1977 contains a quote describing catastrophe theory as the most important development in mathematics since the invention of calculus 300 years ago.
![An announcement of [Christopher] Zeeman's lecture at Northwestern University in the spring of 1977 contains a quote describing catastrophe theory as the most important development in mathematics since the invention of](http://cdn.quoteddaily.com/images/stephen-smale/an-announcement-of-christopher-zeemans-lecture-at-northwestern-university-in-the-spring-of-1977-contains-a-quote-describing-catastrophe-theory.jpg)
