"The greatest mathematicians, as Archimedes, Newton, and Gauss, always united theory and applications in equal measure"

This quote by Felix Klein speaks with the significance of unifying theory and applications in mathematics. He is recommending that the greatest mathematicians, such as Archimedes, Newton, and Gauss, achieved success because they balanced theory and applications in their work. Theory is the abstract study of mathematics, while applications are the practical uses of mathematics. By combining the 2, mathematicians can create powerful services to real-world problems. This quote is a reminder that mathematicians should aim to discover a balance in between theory and applications in their work. It is only through this balance that mathematicians can develop meaningful and enduring contributions to the field.