Principles, Life and Work – Ray Dalio

When I began to look at reality through the perspective of figuring out how it really works, instead of thinking things should be different, I realized that most everything that at first seemed “bad” to me—like rainy days, weaknesses, and even death—was because I held preconceived notions of what I personally wanted. With time, I learned that my initial reaction was because I hadn’t put whatever I was reacting to in the context of the fact that reality is built to optimize for the whole rather than for me.
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This is why many people who have endured setbacks that seemed devastating at the time ended up as happy as (or even happier than) they originally were after they successfully adapted to them. The quality of your life will depend on the choices you make at those painful moments. The faster one appropriately adapts, the better. 24 No matter what you want out of life, your ability to adapt and move quickly and efficiently through the process of personal evolution will determine your success and your happiness. If you do it well, you can change your psychological reaction to it so that what was painful can become something you crave.
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My point is simply this: Whatever circumstances life brings you, you will be more likely to succeed and find happiness if you take responsibility for making your decisions well instead of complaining about things being beyond your control. Psychologists call this having an “internal locus of control,” and studies consistently show that people who have it outperform those who don’t. So don’t worry about whether you like your situation or not. Life doesn’t give a damn about what you like. It’s up to you to connect what you want with what you need to do to get it and then find the courage to carry it through.