I had taken this photo of the youngest niece when she was six months old and sitting in a baby bathtub. She’s fifteen now, and growing into a very personable adult. I looked into her eyes in this photo and had the disconcerting feel that her glance has not changed. I know it is not possible; she did not have control over her head movements then, and her eyes probably did not focus. But somewhere in that glance is evidence of the mind that she has. I’m sure many of you have similar experiences with people you love.
My first thought is that it is a matter of personality. But I read that a personality takes time to develop. Instead, what I think I’m seeing is her temperament; that is the word that experts use for the mental orientation that develops into personality. That probing curiosity, that skeptical openness to new things, am I reading too much into that glance of a six month old? I’ve been with her on too many of her explorations to mistake that. That look in her eyes has not changed.
A person’s mental activities are entirely due to the behavior of nerve cells, glial cells, and the atoms, ions, and molecules that make them up and influence themThe Astonishing Hypothesis, by Francis Crick (1994)
The most believable models of the early development of the brain take us to the very limits of what we now know. Behaviour that we know and recognize is the surface; behind it are layers of processes no one really comprehends. At the bottom of it all is the neuro-chemistry which scientists are beginning to get a handle on. How does the genetics of neurotrasmitter densities map on to temperament? No one knows. This is why the astonishing hypothesis still remains a hypothesis; even after a quarter century of astonishing progress. Part of the problem may be that the question is not precise enough. These are wonderful questions, and they take us right to the limits of understanding who we are. It is a pity that the subject was born so late, I’ll not be alive when it is able to satisfy my curiosity.