The following are names of various defense mechanisms, which different psychologists and psychiatrists often describe slightly differently. Among them are: rationalization, projection, reaction formation, identification, displacement, denial, repression and suppression. There is often overlap between these, and some differences are subtle.
Defense mechanisms are those traits humans have to function in daily life. They are largely unconscious “filters” humans have in order to cope with conflicting feelings and thoughts that occur throughout the day. They include repression of uncomfortable thoughts, rationalization of behaviors, and denial of what one is doing and/or thinking. Because human beings are extraordinarily complex, and live at a much more abstract level of consciousness than other organisms, they have evolved these defenses in order to cope with an immense amount of constant information, much of which the individual will be uncomfortable with knowing.
A great example is global warming. The challenges are overwhelming to the consciousness of most people. There are too many human beings upon the planet right now that are struggling with daily life exacerbated by deteriorated resources. Rather than find obvious solutions, they find ways to blame others (or blame nature) for the problem. They also repress or suppress the problem, put on a positive “face”, or project the problem onto something else, and /or isolate or distance themselves from the problem mentally.
Putting on a positive face is a defense mechanism called reaction formation. It allows people to behave as though there is not really a serious threat to be faced. This can also include the defense mechanism of denial. Examples are having lattes, or lunches in paper or plastic cups and disposable serving ware, when the planet cannot afford it. Another aspect of this is a defense mechanism called Identification. People are able to identify that others are like them, and therefore their in-group cannot all be mistaken, or else people would not consent to waste resources, and so on. Racism, sexism, homophobia, environmentalism, and partisan politics all exist due to the defense of Identification, often mixed with denial and projection.
The defense mechanisms of projection can be thought of as a projector. What a person is unconsciously experiencing, they project that feeling onto others. This is why people afraid of being robbed, cheated, or lied too, are the very ones who steal, and/or lie.
The defense mechanism called regression is simply what happens when a more immature part of a person emerges. This happens to everyone around most family at some time or another, and is rampant at holidays, causing regression back to the familiar, but not necessarily happy, roles of baby, sister, brother and more.
Defense mechanisms are necessary for people to survive. Without the ability to sublimate some human discomfort, all people would be full of anxiety, fight or flight, and mental pain at all times. The difficulty is that people are so gifted at employing defense mechanisms; they do not even know that they do. This leads to hidden conflicts which plague the mind and body, leading to coping behaviors such as addiction, depression, aggression and more. In the situation of global needs, it is dire indeed, requiring that people learn some power and influence, or they cannot improve their situation.
When people take the time to try to better understand their defense mechanisms, they are able to better attend to reality. Every person has defense mechanisms, and everyone uses several each and every day. The only difference with some individuals is that they readily understand they have them.