Neo-classical economics as formulated by Paul Samuelson builds on the maximalization principle to explain much of classical economics. This observation can be understood in terms of modern symplectic geometry, which allows the application of very general techniques to the study of textbook economic systems. We suggest that "income" be considered as a one-form, generating the symplectic structure. In particular, we apply this to take a new perspective on Say's Law and the Phillip's Curve.