At each stage of development the child needs different resources from the family. During the first year, a variety of experience and the availability of the parents for attachment are primary. During the second and third years, stimulation of language development is critical. During the years prior to school entrance, information that persuades children they are loved becomes critical, and during the school years it is important for children to believe that they can succeed at the tasks they want to master.

Although humans inherit a biological bias that permits them to feel anger, jealousy, selfishness and envy, and to be rude, aggressive or violent, they inherit an even stronger biological bias for kindness, compassion, cooperation, love and nurture - especially toward those in need. This inbuilt ethical sense is a biological feature of our species.

After hunger, a human's most important need is to know what is virtuous.

Genes do make a contribution to the IQ score - but a flower needs soil. The environment for poor people is so overwhelmingly powerful, it washes out the genetic effect. There is a genetic contribution to IQ, but you can't detect it when you're living in a deprived environment.

The fundamental problem is that the gap in educational achievement, which is a key in our technological economy, is due in my opinion - and the opinion of many, including Arne Duncan, our secretary of education - to the fact that the families of the poor who are not very educated are not talking to their children, interacting with their children, insisting they do their homework and so on.

All the work on heritability was never based on looking at genes; it was based on the similarity between identical twins or between parents and children. Now that geneticists can look at genes, they can't find genes that account for more than 10 percent of the variation in any human trait.

At each stage of development the child needs different resources from the family. During the first year, a variety of experience and the availability of the parents for attachment are primary. During the second and third years, stimulation of language development is critical. During the years prior to school entrance, information that persuades children they are loved becomes critical, and during the school years it is important for children to believe that they can succeed at the tasks they want to master.