More on my last question: What is the difference between conservative and liberal?

The psychological basis for the two come from upbringing. If one adopts the ideas of a stern father i.e. "make your own way", "look out for yourself", "don't ask for favors"....one leans to conservative. If one adopts the ideas of a nurturing mother i.e. "help those in need", "be slow to criticize", etc....they lean towards liberalism.