In 1960 Eugene Wigner wrote the famous essay "On the unreasonable effectiveness of mathematics in the natural sciences." He marvels on how well mathematics serves as the language of physics. After fifty years the tables have been turned. The fruitful interactions between mathematics and physics have led to numerous examples of physics providing insight into mathematics. I relate this evolution from a personal perspective---both in mathematical content and in comments on the evolution of the interaction between physicists and mathematicians. While the material covers many mathematical bases, I hope the talk will be accessible to a general mathematical audience, including students.