Not only on the face
They say that the face is the reflection of the soul. It’s true that there are people in whom every emotion leaves an unmistakable trace on their face (just ask the Irish actor Cillian Murphy), but it’s not always that easy.
Some emotions have associated facial expressions, but emotions cannot be identified solely by these expressions.
Why? Because the emotions associated with a single facial expression are the basic ones, and these are rarely found in pure form in adults.
To identify emotions in adult humans, we need both facial expressions and nonverbal language
Therefore, if we identify emotions only based on basic facial expressions, two things can happen: either we make mistakes, or we identify only a range of six or eight emotions.
Thus, to identify emotions in adult humans reliably, we must pay attention not only to facial expressions but also to nonverbal language in general.