In the words of Captain Jack – “the problem is not the problem; the problem is your attitude about the problem.” So a reminder or reference point for systems thinking should be useful when faced with the inexplicable or even merely the complex or complicated.The attitudes indicate the preparation of the mind and the body of systemists who have an intention to understand a situation or to act. They reflect the systemists’ knowledge, know-how and experience, their emotional reactions and cognitive positions towards a situation. Conceptualizing these attitudes and organizing them into a set of identified concepts, allows systemists to gain better insight.This book describes a candidate set of concepts for systemy “the study of systems”, framed within what we call the Systems Tree. It is intended for systemists. We use this term for people who have the capabilities to understand complex situations, to cope with the unusual, to identify the right problem in order to solve it and who are able to take decisions keeping in mind a vision for the future. Systemists will, in the future, simply be people trained in systemy.This book describes a candidate set of concepts for systemy “the study of systems”, framed within what we call the Systems Tree. It is intended for systemists. We use this term for people who have the capabilities to understand complex situations, to cope with the unusual, to identify the right problem in order to solve it and who are able to take decisions keeping in mind a vision for the future. Systemists will, in the future, simply be people trained in systemy.Within the topics of the book we explore the need for systemy, the branches of systemic attitudes, thoughts and the underpinning concepts of systems that we mentally grapple with when we try and interact with them. As we explore these relationships, we look across “intentionality”, “fruitful thinking”, “traps in thinking”, “systemy in action” and the acquisition of knowledge.