The document discusses systems thinking and its impact on decision making. It begins with introductions to systems concepts and definitions of systems thinking. It describes the difference between system 1 and system 2 thinking, with system 1 being fast, automatic thinking and system 2 being slower, effortful thinking. It emphasizes that in today's complex and interconnected world, systems thinking is needed to understand complex problems and avoid unintended consequences of decisions. Systems thinking provides a holistic view rather than a narrow, reductionist view to help make better decisions. The document provides examples of applying systems thinking in various domains and argues it is a new way of thinking needed to address challenges of the current century.