M Jackson

Sigils, seals and pentacles are occult devices used in ceremonial magic as part of the invocation and evocation of angels, demons and other spirits. They were developed out of ritual magic, a mixture of Greco-Egyptian Hermeticism, Arabic Astrology and Jewish Cabala in the 10th century Medieval Europe. These forms of magic practise were raised to the level of a science and studied as such during the Renaissance. Magicians recorded their designs in magical training books called grimoires, such as The Key of Solomon and many others. Four centuries later, modern interpretations of such designs continue to feature in post-modern grimoires such as the Necronomicon. This collection of occult designs is a fascinating insight into the inner world of the magician and the entities he may call on, for better or worst.

A piercing poetic experience depicting vigorous controversy and conflict stemming from the affliction of life, love, happiness, pain, intimacy, and disappointment.

Software Reqiuirements and Specifications is the latest book from Michael Jackson, one of the foremost contributors to software development method and practice. The book brings together some 75 short pieces about principles and techniques for requirements analysis, specification and design. The ideas discussed are deep, but at the same time lightly and wittily expressed. The book is fun to read, rewarding the reader with many valuble and novel insights. Some sacred cows, including top-down development, dataflow diagrams and the distinction between What and How, are led to the slaughter. Readers will be provoked--perhaps to fury, perhaps to enthusiasm, but surely to think more deeply about topics and issues of central importance in the field of software development. There are new ideas about problem structuring, based on the concept of a problem frame, leading to a clearer notion of complexity and how to deal with it. And other important topics include: Principles for evaluating development methods New approaches to capturing and describing requirements and specifications, based on the relationship between the software system and the problem context The technology of desciption in software, including new ideas such as designations, the separation of descriptive moods and the scope and span of description Incisive information about the proper role of mathematics and formalism.