Through positive thinking and related approaches, we seek the safety and solid ground of certainty, of knowing how the future will turn out, of a time in the future when we'll be ceaselessly happy and never have to fear negative emotions again. But in chasing all that, we close down the very faculties that permit the happiness we crave.
Psychology, Positive Thinking
For the Stoics, then, our judgments about the world are all that we can control, but also all that we need to control in order to be happy; tranquility results from replacing our irrational judgments with rational ones
Happiness, Mind
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