"Nature conceals her secrets because she is sublime, not because she is a trickster."
In considering causation in his conclusion to The Evolution of Childhood, Melvin Konner writes:
When asked why a teenage boy punches another, we can say that he does so because of:
- the secretion of a neurotransmitter in the amygdala
- in a neural circuit primed by testosterone,
- in response to a verbal insult,
- after a lifetime of frustration and observation of violence,
- given a fetal brain hurt by alcohol,
- and shaped by prenatal androgenization,
- against a background of maleness and individual aggressiveness,
- caused by natural selection favoring male status and self-defense,
- on a phylogenetic foundation of reproductive competition.
None of these explanations contradicts any of the others; in fact, we do not have an explanation until we have all nine levels.
This is an impressive illustration of over-determination, and an integrative understanding of a seemingly simple act. There is the full spectrum from molecular biology to cultural narrative; if a discrete behavior is this complex, how can we hope to answer the question, "Doctor, why am I depressed?" However, because we must be pragmatic creatures, we can't just throw up our hands; we must decide which cause(s) will be most significant for us in terms of possible intervention. However, we may not have sufficient information for such decisions for a few lifetimes yet. Discussing the biochemistry of development, Konner goes on to write:
Now all we have to do is spend a couple of centuries working out the cascade. We will need a very big piece of paper--it won't fit on a laptop screen--but we will eventually draw it, and it will explain everything. Up to a point. Beyond that, there is chance, chaos, and countless outside influences, especially in the flexible realm of behavior. These may make our elegant diagram look like a Jackson Pollock painting. Still, these outside influences are partly lawful, just as Pollock's drips and splatters, a mess to the untrained eye, are strangely ordered and intentional in their provenance. These external forces, like the cascade itself, are powerful, and understanding them better will give us a certain measure of control.
Nevertheless, we now know that it is foremost the cascade that builds brain and behavior, not just in the embryo but throughout development and life; the cascade proposes, the environment disposes. The cascade is the key creative element in the story. So we behavioral scientists might now show our respect for it--and break decisively with a century of disdain--by enunciating a law of psychogenetic inertia: developmental plans in motion will stay in motion according to predetermined guidance unless diverted by outside forces. It is perhaps just another way of saying canalization, and it is hardly as elegant as Newton's first law, but it may serve to remind us that all creatures, children included, come into the world with a plan.
A new human being is like a cupful of water dipped from the Amazon--we may straighten its course here and there, or dredge its bottom, or purify its waters but there is no need for chlorine or a canal.