Rolling on and folding out
I realized recently that I often make use in my own thought of a distinction that isn’t commonly recognized: that between evolution and development. So I thought it would be worthwhile to set down what I mean by these two terms.
I derive this distinction in part from John Henry Newman’s Development of Christian Doctrine. (Incidentally, when papal encyclicals in the late 19th century condemned the view that doctrine evolves, many took this to be a condemnation of Newman’s book—but Newman’s theory of doctrinal development is now considered to have been foundational for Vatican II, so if there is any continuity at all between the pre- and post-Vatican II Church, this distinction better hold water!) In that book Newman distinguishes between the development of a single entity over time, and the replacement of that entity by another, related entity. Take Newman’s example of the Roman Republic: it developed in various ways over a span of several hundred years, and then in the time of Augustus was replaced by the Roman Empire. An entity can change, and indeed must change, so long as the changes do not change the entity’s substantial nature. The changes, moreover, have a direction: a frog does not turn back into a tadpole.
Newman’s book is all about how to recognize the identity between frog and tadpole; he offers little theorizing about what is going on when Empire replaces Republic. Here we look to Charles Darwin, and his theory of evolution via natural selection. The key thought is that there never exists an individual in a vacuum; rather, there exist many, competing individuals, all members of the same species, but all slightly different from one another; and when a new individual comes into being, it is related more closely to some individuals than to others. Over time, the characteristics that predominate in the group, turn out to be the characteristics of those individuals who managed to outcompete the others by producing the most offspring. Unlike development, the “subject” of evolution is not the individual, but the species. But, of course, a species can also be considered as an individual, just an immaterial one, and immaterial v material is not the key difference here. Rather, the key difference is that, for Darwin if not for Aristotle, a species has no nature of its own, but rather is defined only as a set of biological individuals are able to reproduce with one another. Given enough time, a group of rats could be made to evolve into a group of monkeys, and (a point not always recognized) that group of monkeys could be made to evolve into a group of birds, or crocodiles, or anything, really, if the circumstances are correct. We can posit that the group retains its identity across time because it would always be possible to draw a chain of heritage and potential interbreeding between any two members, but no other characteristics of the group are necessarily preserved.
So, to summarize the distinction—which, happily, coincides with the etymologies of the words—evolution (=rolling on) means “altering the composition of the group in accordance with changed external circumstances”; development (=folding out) means “unfurling the nature of the substance according to fixed internal principles”.
According to Newman and Darwin, both forms of change are produced by internal conflict: evolution, through individuals competing against one another to populate the set; development, through individual parts competing against one another for control of the whole. But these are different kinds of conflict, and they generate change in different ways. For Darwin, the conflict is accidental. Even if two members of a species compete directly with one another for a given resource, the conflict is about that resource, not about the species of which both are members. Members conflict with one another in just the same way they conflict with non-members, and we can see that their conflict is “about” the species only in that it affects the species’ trajectory, and can even, if there ever occurs a large enough divergence between subpopulations, lead to speciation. For Newman, on the other hand, the conflict does not just happen to determine, but is actually about what the organism will do next. It is best understood as a form of productive tension. Absent a connection to be tensed, the conflict makes no sense, and so if the two parties to the conflict ever reach the point of having nothing in common, the organism has not been split in half, it has ceased entirely to exist—it has died.
I’ll close with some examples of evolution and development:
Biological species, as already discussed, evolve through competition between their different members, while biological individuals develop through the tension established between various body parts. When the members of a biological individual begin, not just coming into productive conflict, but actually competing, we call that cancer. And when any subset of a biological species stops competing, we start thinking of it as analogous to an individual—for example, in a beehive.
The civitas terrena evolves: different regimes in different lands rise, fall, war with one another, and inspire one another’s politics. The civitas Dei, on the other hand, develops: the Church is a single organism, and its parts may strain to move it in different directions, but any civil war within it would be a scandal. This is, incidentally, the reason why federalism can be good idea in secular politics, but not in ecclesiology. Evolution requires experimenting and seeing what works, with little any imposition of top-down authority. Development, on the other hand, cannot abide experimentation: the activity of every member affects every other member, and it is impossible to just “do one’s own thing” without damaging the unity of the whole.
Economic markets evolve. Economic agents, even “fictional” agents like corporations, develop. Attempts to establish an artificially selective environment in corporate settings tend to backfire, since it encourages workers to compete against one another directly, as individuals, rather than to come into conflict only when they disagree as to the good of the firm. Of course, a corporation can undergo many transformations, beginning as a small-town soap manufacturer and ending as a global conglomerate. This is perhaps because corporations are only analogous to agents, and so can undergo transformations that would mean death for any substantial individual. Or perhaps it reveals the true essence of that particular structure of corporation, as a pure profit maximizer. But either way, we still need to draw a distinction between this kind of transformation, which is at worst a perversion of development, and evolution, which is another thing entirely.