The “mimetic theory” is an expression used to describe the core of René Girard’s work. But it should be noted that there is no “mimetic theory” constituting an ensemble of principles that would be a finite interpretation of a given topic. Girard himself only uses this expression by lack of a better one to talk about his own work.
Girard’s work is an anthropology. This means that he is aiming at explaining the elements that we can consider to be specific to the human species.
This specificity is described, based on anthropological and ethological observations, as a more intense tendency to imitate the desire of others in man than in other species.
This tendency is called “mimesis of appropriation”, and the desire resulting from this imitation “mimetic desire”. This means that we will want to possess what we think the others want to possess. If we see someone wanting to appropriate something, we will start desiring it too, by imitating (what we consider to be) his existing desire.
If a kid takes a toy, the kid next to him suddenly wants that exact same toy.
This process leads to violence because it has a simple consequence : if two individuals desire the same thing, they become rival. This is also present in the animal kingdom, but is kept under smaller proportions by the animal structuring of society, based on relations of dominance. The closest example of the mimesis of appropriation found in man, is the one observed in greater apes. In humankind, the structuring of violence does not stop in the way it stops in the animal kingdom. It is more intense and can lead to death.
This intensity of mimetic desire means that violence is of primal importance in the development of human communities. From a Darwinian point of view, early human forms of communities had to find a way to keep this source of violence under control.
In hundred of thousands of years, mankind slowly built a strategy to cope with the increase of violence inside communities. According to Girard (and, in fact, anthropology in general), that strategy was the creation of rituals of sacrifice. By sacrificing a scapegoat, a group can unanimously accuse that victim of all evil, and via his death, purge the community of that violence.
Sacrifice is here understood as a mean to lower the level of inner violence in a group, since the death of the scapegoat - from the perspective of the perpetrators - expels the violence outside of the group.
Sacrifice, as we can etymologically see, is as the source of the Sacred. According to Girard, the fact that religions are found universally on earth, in every culture, and that all of them present rituals of sacrifice, is a data that has not been explained by traditional anthropology. And it shows that sacrifice is a fundamental “institution” of mankind.
Girard indeed associates sacrifice with the birth of “culture”. His concept of “culture” is defined by the existence of interdictions (rules, such as “do not steal”) and rituals (sacrifices, real of symbolic, of a victim).
The “mimetic theory” explores, as a method and a hypothesis, the forms of culture trying to understand the nature of violence found in it, and the ways it is developing to cope with it.
Today, a lot of work is being done in understand our own culture, called modernity (or post-modernity), with the help of the mimetic theory.
According to Girard, modernity is ambivalent : it is both an emancipation from the sacrifice, and also the risk of seeing archaic forms of rituals re-emerge inside modernity itself, without being detected as such.