Why does focusing on gratitude and positivity have such a big impact on finding inner peace?

Is the manager flirting with me again? He asked me if the pancakes were good and I said I’m pretty sure. He was like so you’re very pretty and sure. I like your confidence.
What mindset shifts can help INFJs smile at chaos rather than seeing it as a personal failure?
Do you find that you learn more about human nature by watching a comedian or by reading a sociology textbook?