It is commonplace in philosophy and psychology to divide emotions into two groups: basic and complex emotions.
Basic emotions, which include sadness, anger, fear, disgust, contempt, joy, and surprise, are so-called because they are associated with universally recognizable facial expressions (see image). In disgust, for example, you see a raised upper lip, a wrinkled nose bridge, and raised cheeks.
Although basic emotions are sometimes accompanied by unique facial expressions and behavioral responses, there is no one-one correspondence between emotions and how they appear. Take the universally recognizable facial expressions. Very talented actors can mimic these facial expressions without having the associated emotion. Conversely, most of us are masters in suppressing facial expressions accompanying emotions. You might feel genuinely sad, yet put on a big smile before entering your workplace, thereby deceiving your colleagues into thinking that you are cheerful.
Even when our emotional expressions reflect our inner mental life, they need not be universally recognizable. This is because the basic emotions can trigger many other expressions besides the unique facial expressions, physiological responses, and tendencies to act. Examples:
- Intense sadness might give rise to a facial expression nearly indistinguishable from anger or rage.
- Mild sadness may not look like anything at all.
- When several emotions are simultaneously present, one of the emotions may dominate and show up on your face.
- When emotions last for a long time, they pop in and out of your conscious awareness. When you are not aware of them, It is much harder to detect them.
Basic emotions likely have made significant contributions to our survival since the beginning of human history. When understood in this sense, “basic”—as it occurs in "basic emotion"—just means primordial (evolutionarily basic).
But if an emotion is truly basic, how could it have more basic components? Take surprise. We can split surprise into two responses: one is a positive sense of interest and wonder, and the other is a negative feeling of panic. Why call surprise "basic" when it's composed of other emotions?
The reason for this is that "basic" does not mean "lacks components."
In fact, complex emotions vary a lot in what they are like in different people, situations, and cultures. Although grief is often taken to be a blend of surprise, denial, sadness and anger, grief can be entirely different in some people or cultures. For example, some people grieve a loss without ever showing anger. Others grieve by being absolutely furious.
Grief is often said to be composed of surprise, denial, bargaining, fear, anger, sadness, and acceptance. These components are not usually present all at the same time during a grieving episode but tend to occur sequentially and not necessarily in the order I just listed them in. Although grief can involve these building blocks, it can be manifested in numerous other ways. If the loss was expected, surprise may not be a component. If you are grieving the death of a loved one, the grief may not involve denial or bargaining. If, by contrast, you are grieving a breakup, you may go through long periods of denying that the breakup really is a breakup and ferociously negotiate and bargain with your ex. Grief can also involve alterations in mood, including feelings of depression, despair, melancholy, irritability or anxiety as well as temporary changes in the manifest features of personality, for instance, shifting toward isolation, insecurity, emotionality, and vigilance.
It’s likely because complex emotions can be a blend of different mental states in different people, situations and cultures that they do not give rise to a facial expression that is universally recognized.