English pewter English pewter While the term pewter covers a range of tin-based alloys, the term English pewter has come to represent a strictly-controlled alloy, specified by BSEN611-1 and British Standard 5140, consisting mainly of tin (ideally 92%), with the balance made up of antimony and copper. Significantly, it is free of lead and nickel. Although the exact percentages vary between manufacturers, a typical standard for present-day pewter is approximately 91% tin, 7.5% antimony and 1.5% copper. By the 15th century, the Worshipful Company of Pewterers controlled pewter constituents in England. This company originally had two grades of pewter, but in the
The purpose of a system is what it does be balanced by a more straightforwardly descriptive view. The term is used in many fields including biology and management. The purpose of a system is what it does The purpose of a system is what it does (POSIWID) is a systems thinking heuristic coined by Stafford Beer. Stafford Beer coined the term POSIWID and used it many times in public addresses. In his address to the University of Valladolid, Spain, in October 2001, he said "According to the cybernetician, the purpose of a system is what it does. This is a basic dictum. It stands for bald fact, which makes