when you boil it down, there really is no formula to reaching adulthood. for some, we are thrown into the midst of it by our circumstances. for others, we simply wake up one day and realize that we are no longer able to (allow ourselves to) get away with the same shit that we used to be able blame on adolescent immaturity.
our culture even sends mixed messages—we're told to 'grow up,' all the while being encouraged to remain a 'kid at heart.' throughout our childhoods, we're told that being an adult is no fun, that it's full of responsibility, and that after your 20's, every five years pass like five days. besides, how do we know when we've finally 'grown up'? perhaps that's just a riddle with no clear-cut solution. (it may not even be possible to be fully 'grown up' all the time, nor would that be seen as desirable.)
indeed, we are in disagreement (and act in indecisive accordance) with regards to the classification of 'adult.' for some, it seems odd that 18-year-olds wielding machine guns in the military are not allowed to drink. consider then the unemployed 25-year-old who lives at home and off his parents' money. should he be allowed to hit the bars and get plastered on a consistent basis? imagine another case in which a 28-year-old college dropout 'works' at his dad's company, lives in a condo his parents don't currently use, and expenses everything to his trust fund. by many standards, he is fully considered an adult, but has he reached adulthood? it all depends on whom you are speaking about and to whom you are speaking.
for now, I associate emerging adulthood with independence—the ability to be self-reliant in thought, finances, and actions. and I equate adulthood with maturity—the acknowledgement that things can't (and shouldn't) always be 'me-me-me' combined with the wisdom to wholeheartedly accept happiness and the pursuit of happiness. to realize that we are still somewhat immature, I think, is a step toward 'growing up.' self-discovery is lifelong—not just limited to something we do in our 20's. some parents don't consider their kids to be adults or 'fully grown' until they get married and start their own families. if their kids are ok with that classification, then what's the problem? what if part of adulthood consisted of living at home (as is customary in other cultures—e.g. Italy, India)? wouldn't that just engender a greater appreciation of family and family values in our society?
as with anything, the more we think and learn, the more we think that we need to keep learning. we in the US have the luxury of experiencing 'emerging adulthood,' and it's precisely due to this luxury that such a distinction even exists. but while all this must be interpreted through a uniquely American lens in the context of our current times, I can't help but think that, at the core, aren't we all still made of the same stuff?