Mathematical economics is compared and contrasted with mathematical engineering. Engineers use mathematics where it is practical and cost-effective, sometimes cutting corners, and leaving theorems and derivations to professional mathematicians. In contrast, papers by mathematical economists are often loaded with theorems and lemmas, with only the slightest suggestion that human affairs are involved. I conclude that some economists have fallen for the romance of mathematics, as engineers occasionally do, and that considerable time and talent has been wasted in the process.