The work is done simultaneously in both worlds: We achieve external goals through internal balance. The Stoic philosophers called this state "apatheia," meaning a state "free from passions." To reach this wonderful achievement, a person needs to develop – firstly – two important skills: self-observation and the realization of internal knowledge. For the ancients, all the knowledge we need is already within us, and all that is required is to discover it. Through self-observation, we can learn our psychological mechanisms, while through "reflection" (a process similar to what we call "meditation"), we can retrieve internal knowledge from these mechanisms. Through these abilities, Stoic philosophers could control the interpretations they gave to external events, reaching "apatheia." As "apatheia" became the dominant mindset within them, they approached the much-desired happiness.