Epictetus said, “Men are not influenced by things, but by their thoughts about things.” The Stoics are known for their control of their emotions and their reactions to internal and external stimuli.
The Stoics are often thought of as men that felt no emotions. This is a false assertion, The Stoics believed that one should recognize their initial emotional response to a stimuli and react accordingly. The brief moment one takes to reflect on the initial emotion invoked and then accurately choosing the subsequent output in the form of a reaction is the key.
Think of a human mind as a converter akin to a Marshall amplifier that has a plugged in electric guitar. Something that is taking the initial input in, modulating it, and delivering a powerful output. We are constantly fed inputs that elicit emotional responses. It is our duty to modulate the inputs to deliver the correct, rational, and measured outputs. This step is often overlooked as the amount of inputs encountered each day can be overwhelming, that is why many of the input/output cycles occur subconsciously. It is easier to passively internalize things and respond without taking the time to realize what has occurred.
It takes time and discipline to make the the Stoic way of recognizing the input, analyzing the initial emotional response, and choosing the rational output as the default. Personal defaults are key, as they are the decisions revisited time and time again. A default is a preselected decision taken when other alternatives are present. Modernity provides myriad options in almost all areas of life, which leads many to make poor decisions. It is idealistic to think that the correct decision will be selected in all situations, in Economics this fictitious entity is titled homo economicus, the person that makes the most rational decision in each situation. Humans do not function like homo econmicus and often make the wrong decisions heavily influenced by emotions. That is why defaults are tremendously important.
In sum, one should take the time to practice the Stoic discipline of consciously recognizing inputs in the form external stimuli, analyzing initial responses, and actively selecting the rational outputs. Master your emotions because emotions cloud reason and reason demands clarity.