Human never have any perfect idea

Civil right moment, industrial revolution , and education reform have improved the society in United State. Therefore , some says that it has no fractious elements. Well,  the phrase,"nobody's perfect" is to hackneyed to say, but people keep  saying it for a reason. Because mankind always or rarely make mistake in their life, the theory they make somehow contain their tragic flaw . As everybody know, no political theory is considered to produce salutary effects in a society in a long term. Likewise human can't be good forever on account of the situation affects  them, although they intend to do good thing.