Fred Brooks’ retelling of the biblical story of the Tower of Babel offers many insights into what makes building software difficult. The difficulty, according to common interpretations, comes from the communication and organizational problems in software development. But the story contains one more important lesson that people tend to miss: one cannot accomplish impossible goals, which programmers are often asked to do. Software engineering, as a discipline, can overcome poor communication; but as long as we attempt to live up to impossible expectations, we will always fail. Categories and Subject Descriptors K.6.3 [Management of Computing and Information Systems]: Software Management—Software development; K.7.m [The Computing Profession]: Miscellaneous—Codes of good practice General Terms Design, Documentation, Economics, Human Factors, Languages, Management Keywords communication, documentation, engineering, programming, science