Roller coaster phobia combine substantial heights with seemingly insignificant support, as well as free-falls and the illusion of uncontrolled drops. Because acrophobia involves an extreme fear of heights and falling, these conditions could cause someone who is an acrophobic to have an extremely negative reaction to riding roller coasters. Claustrophobia involves two parts, fear of physical restraint and fear of suffocation. The safety harnesses and enclosures on some rollercoaster and other rides are very restrictive, in order to protect the riders from harm. In addition, the speed of these rides can cause air displacement that makes it difficult for riders to catch their
The purpose of a system is what it does 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 a better starting point in seeking understanding than the familiar attributions of good intention, prejudices about expectations, moral judgment,