>> There are some principles of development.
These are kind of basic underlying characteristics
of development that as a field there's been general
consensus upon.
So let's look at each of these.
So the first is that development is lifelong.
So we know that there is change from conception to death.
And we only look through adolescence in this book,
but we do know that early experiences are
really important.
We also know that development is multidirectional.
It's not a clean, neat, kind of upward sequence all of the time,
that we will show gains in some areas and losses in others.
So every developmental milestone that we reach exhibits those.
We know that development is multidimensional.
The physical domain includes changes in height and weight,
gross and fine motor skills, sensory capabilities,
the nervous system, as well as kind of health and wellness.
In the cognitive domain, the changes are in intelligence,
wisdom, perception,
problem-solving, memory, and language.
And in the social and emotional domain or dimension,
the changes are related to emotion, self-perception,
interpersonal relationships with families, peers, and friends.
We also know, very thankfully,
that development is characterized by plasticity,
which means that we are -- children especially --
are able to overcome great adversity.
So this picture, for instance, is a child in Haiti.
And the pictures on the left and right are only two months apart,
and you can see what happened.
He went from being 12 pounds to a healthy four-year-old,
I believe, with just a little bit of good nutrition.
And so we know that when given optimal situations, again,
development can often go back to what it would be --
would have been without the risks.
And we also know that development is multi-contextual.
So we know that nature and nurture are both important
and that the fact that where we live and the things that we do
and believe are a response to the things around us.
And so there's this kind of interplay and kind
of real deep contextual situation around development.
And so we have to be thinking about that bigger picture
when we think about development.
It's not just a matter of, you know, our genes or environment.
The analogy that I like to use when I think about this is kind
of that often kind of our genes or our situation are the recipe,
but how closely that recipe is followed will greatly impact
the outcome.
So these are just a few of the things that we agree
on regarding development.