Give me the child until 7 ...

Beliefnet
The cerebral cortex, that which makes humans sapient, isn't fully developed until two and is overdeveloped at that point until about 8yo.  It is extremely plastic in those years and much of what is necessary for social living is learned in those years.  The mores of the tribe via the family are essentially set by 8.  Or why the Jesuit's mantra is "Give me the boy until he is 7 and I will give you the man."
The "Whys" begin at two and the answers will largely determine the mold the brain of the child will conform to.  Authoritarian answers: "Because I said so," or "Because God says so," will condition the child to expect to be told what to do and not think for hermself.  Social conforming answers: "Because people expect you to do that,"  "Jesus will love you if you do that,"  "Our family or tribe does it that way" will condition the child to be aware of social cues to behavior but allow for some flexibility as social cues are seldom consistent.  Child centered answers: "Because you will be happier if you do it that way," "Because it is good for you," "You will have more friends if you do it that way" will condition the child to take responsibility for herm actions and consider the effects on self and others of behavior. 

These are but points on a continuum with lots of overlap generally centering on social conformance.  We are after all a social animal.  There are of course outliers on both ends, extreme self-dependence, and fundamentalism but most will be socially conforming.