The traits the word 'childish' addresses are seen so often in adults that we should abolish this age-discriminatory word when it comes to criticizing behavior associated with irresponsibility and irrational thinking.
In the highest antiquity, the people did not know that there were rulers. In the next age they loved them and praised them. In the next they feared them; in the next they despised them.
There is only one thing that stands in our midst, attenuated and threatened, but enthroned in some power like a ghost of the Middle Ages: the Trade Unions.
In this day of wonders no one will say that a thing or an idea is worthless because it is new. To say it is impossible because it is difficult is again not in consonance with the spirit of the age. Things undreamt of are daily being seen, the impossible is ever becoming possible.