“As we age and plasticity declines, it becomes increasingly difficult for us to change in response to the world, even if we want to. We find familiar types of stimulation pleasurable; we seek out like-minded individuals to associate with, and research shows we tend to ignore or forget, or attempt to discredit, information that does not match our beliefs, or perception of the world, because it is very distressing and difficult to think and perceive in unfamiliar ways. Increasingly, the aging individual acts to preserve the structure within, and when there is a mismatch between his internal neurocognitive structures and the world, he seeks to change the world. In small ways he begins to micromanage his environment, to control it and make it familiar. But this process, writ large, often leads whole cultural groups to try to impose their view of the world on other cultures [...]”