The machine metaphor is deeply rooted in western culture and complex systemsin nature and society are often interpreted in such terms. With the advent of electronic computers, the machine metaphor applied to thinking and to thebrain has become even more pertinent. The idea of a machine has itself changed over time. In this book these transformations are made transparent, various aspects of the machine metaphor are discussed and limitations and pitfalls of the metaphor are elaborated. The chapters are written in a non-technical fashion and are accessible to a large audience ofscientists and also to laymen interested in the scientific perspectives and logical foundations of the machine concept that has been so influential in western thinking.