The Principles is the handbook by which, Ray Dalio, an ace investor created an organisation that became an epitome of success in past three decades and is built to last beyond its recent successes. The book operates at multiple levels, on the one hand, it is a professional who strives to excel in his chosen field and on the other hand, about the organisational dynamics. Ray advocates working based on principles – hence the title of the book – coupled with humility and open-mindedness by continuously aligning oneself to what one wants to achieve, the efforts necessary to unearth the facts, and what should be done to achieve the goals in light of circumstances. In this, being believable and believability-weighted decision-making is the touchstone. The method envisaged is to treat the complex organisational systems is a vast machine, by comprehending cause-effect relationships, writing down the principles, and using computer-based algorithms (data driven decision making where the principles are validated based on ever changing environment and facts) to help make decisions. Algorithms based input and output models will not only suffice but test them through smart, believable people (importance is given to character, creativity, and common sense, more than their experience – but having strong track record, having clear headed explanations and solutions) holding contrary views, backed by facts and reasoning, and continuously develop, test, and systemize the timeless principles for upsizing the gains while reducing the downsides. The process looks into first order consequences, as well as the second and subsequent order consequences. The process of putting honest thoughts on the table, thoughtful disagreements, and agreed upon ways of deciding (voting, clear authorities, etc.) also requires oneself of being curious enough to see from a different perspective than our own, leading to a richer and valuable perspective. To do so, get the problems and disagreements on the surface (Bridgewater has a concept of error-log – wherein all errors are to be listed by the person responsible, which is an institutional response for avoiding spin), to learn what can be done. The process also helps to protect the downsides for it helps the successful people (i.e. dreams + reality + determination) to change their ways or continuous adaptation (the key is to fail, learn, and improve, summarizing a formula: pain + reflection = progress) by allowing them to take advantage of their strengths while compensating for their weaknesses. The book is full of investment and worldly wisdom and his journey of creating Bridgewater. For one, Ray describes how he came to his investment thesis of making few good uncorrelated bets, which are balanced and leveraged well. Second notable one, the looping personal evolutionary process – requires one to be flexible and having self-accountability, and devoid of ego and blind spots– by setting clear goals, identifying the problems for resolution, the identification of causes, design plans and push for completion. Thirdly about avoiding getting attached to one solution or idea, leading to mental pain, and resulting in a wrong decision. Fourth, decision-making process –involve smart, believable persons, and then not to believe everything one hears, step back to gain perspective, try to make a pattern of events to understand the level at which the problem exists, flow charting the thought process, simplify, etc. Fifth about great organizations – which entails having both great people (with character and capability), and great culture (to bring to fore the disagreements and resolve them). Stress on idea meritocracy = Radical truth + Radical transparency + believability weighted decision making). Making people accountable, when the culture provides for sharing of information and transparency – making it a two-way street. Spend lavishly on time and energy for getting people in sync. The book is very comprehensive as it covers virtually every issue that an individual or an organisation tends to encounter and the means to manage or overcome the circumstances and challenges. Overall the book is a must-read not only for entrepreneurs, students of management and leadership, and also, the knowledge workers.