If you were to cast your eyes over some of the writings of Stephen Jay Gould you would find him picking a fight with the concept of Phyletic Gradualism. Gradualism is the idea that species adapt gradually to their environment and that this rate of change is so slow and even that it does not really make sense to speak of there being real differences between ancestral species and descendent species. Under Phyletic Gradualism, different species reflect our knowledge of the fossil record and not the realities of evolutionary history. Gould argues instead for a model known as Punctuated Equilibrium. A theory that posits that most species do not change at all and that when evolution does occur, it occurs rapidly and locally. Daniel Dennett and Richard Dawkins have responded to Gould’s arguments by pointing out that nobody, not even Darwin, has ever subscribed to the model of Phyletic Gradualism Gould attacks in his popular writings.
As we see from Dawkins’ memes, the process of evolution is a neat metaphor for other forms of change. Indeed, some thinkers have used the theory of punctuated equilibrium to explain how institutions react to change. But the model could also be applied to individuals as a means of understanding the process of psychological change : People develop understandings of themselves and their surroundings and, over time, these understandings cease to apply. So people allow their ideas to evolve. They adapt their images of themselves and their ideas about the world to suit the new environment. They adapt. They evolve.
One of my favourite things to do when watching a drama is try to work out whether the writer is an emotional Phyletic Gradualist or a Punctuated Equilibrist : Does the drama present emotional change as a slow and gradual process or does it suggest that we exist in a state of emotional and psychological stasis until the levee breaks and we have to evolve in a hurry. However, as with biologists, the best writers are those who do not allow themselves to be trapped by artificial dichotomies. They allow for the idea that people change at different rates and in response to different forms of pressure. They do not distort their characters’ psychologies in order to slot them neatly into a narrative. Mia Hansen-Løve’s Le Pere De Mes Enfants is an example of this kind of drama. It is a film that deals with drastic and sudden emotional change but rather than seeking to pin the process of evolution down to a question of Big Events or Epic Journeys, it contents itself with showing us a few moments along a path travelled at different rates by different people. It also calls into question the vocabulary used by film-makers to communicate these rates of emotional change.