Some economists claim, although I partially disagree, that by creating a strong middle class you also create a strong lower class. The richer the middle class is, the better conditions will be created for a lower one. But the mere existence of a class of people who will be deprived of what the society may offer and are REQUIRED to exist so this society can exist is the main proof that capitalism can never, ever generate a perfect society. On the other hand, socialism can, but only teorically, as it goes against the main nature of human beings - at least, most of them.