The range of emotions a person can experience is limited by their emotional granularity – the ability to construct and identify more precise emotional experiences.
Everything your body does, inside or out, requires energy. To manage its “body budget” across hundreds of body parts and billions of cells, the brain has to constantly predict the body’s energy needs. Many of these “budgetary changes” we experience as emotional experiences.
Six steps to improve your emotional granularity: try on new perspectives, recategorize what you're feeling, talk about what you're feeling, move your body, improve your vocabulary, write about your experiences.
The brain uses concepts to make sense of data. Emotions like “fear,” “sadness,” and “disappointment” are concepts just like any other. Just as your brain interprets a pattern of light as a “window,” it might interpret a pattern of bodily sensations as “fear” or “disappointment.”