Goodreads: The Blank Slate: The Modern Denial of Human Nature by Steven Pinker (checkpoint 5)

Audiobook: 5hrs 7mins/ 22hrs 42mins

Chapter 4 discussed how culture is not completely independent of our biology.  It is not a separate entity existing "out there".  He asserts that we aren't so much shapped by culture as we actually shape our culture ourselves, from our biology. 

Chapter 5 has been discussing how neurons, genes, and environmental factors such as experience all affect our decisions, behaviors, and the like.  He recognizes an interplay between Nature and Nuture for our behaviors, but it is mostly vastly different from the publically acquired understanding of it.
There are many points of discussion that make sense to me, while others, from my vantage point, seem to be taken too far.

For example, his main line of discussion is that we are much more affected by our biology (genes, neurons, etc) than we are our culture.  There have been studies where twins are separated at birth and grow up in completely different familes and environments.  When they finally meet each other face to face years later, they feel like they've known each other all their life, because they are so similar.  Same genes, different environments.  Biology seems to have won out.

There are other studies that take children from vastly different families and raise them in the same environment.  There were big differences in between the two kids even though they were raised in the same environment.  These are very shortened examples that don't go into further detail of the factors at play, but biology seems to be the largest factor for behavior, skills, etc.

The important thing is that biology is not everything, although it can be very important.  If you take a child and raise him in a good environment versus a bad environment (however those are defined), we would suspect there would be very different outcomes for how that child makes decisions and behaves. 

I don't think Pinker would disagree at all with this, but I get the feeling that biology is near everything, and in many senses it is, at least for a foundation of ability.  I have a feeling that he may be pushing it so hard to counter-act the other extremists that don't believe biology has much to do with it at all, namely that the environment is everything. 

Intuitively, I currently side more with the proponents declaring that the environment is so important.  However, I also recognize that biology can present real limiting factors.  I think biology gives us our baseline, and the environment can either utilize the maximum ability or leave it untapped.