It's hard to generalize, especially when the terms are undefined. Is a "young" adult 22, and an "old" adult 45? At 45, we are generally a little wiser than at 22. I certainly was. But if "young" is 45 and "old" is 80 does that still hold true? At 80, we don't have much future left and some of the wisdom needed at earlier ages is not so relevant. There's no easy answer, especially when the question is so broadly stated.

In some cases. You know the term, there's no fool like an old fool. Then again, with age comes experience. It all depends on who is in question.

No, they just think they are.......

As an old adult, I assert you should have posted this as a poll. . .

Depends on how you define "wiser"

There are always statistical outliers and all definitions depend on individuals and subject matter but there may be a trend that suggests:

"showing experience, knowledge, and good judgment": Probably a greater aptitude. Every years I have countless experiences that change who I am, how I evaluate the world and others. I am not the same person I was in my 20's and if given the opportunity to revisit mistakes of the past, would not waste so many years trying to fix the un-fixable. I see the world as a different place now. Years of experience have molded this perception and I can not envision establishing this perspective with anything less then many years of encounters and events.

"responding sensibly or shrewdly to a particular situation". Possibly (much less likely then the first definition)

"having knowledge in a specified subject." depends entirely on the topic/individual.

...not yet

That is a pretty sweet question coming from a 21-year old. I think some are, sure. I certainly thought myself wise at your age, but now I think myself not wise at all.

Depends on the individual.

Some people are wise beyond their years.

Some people never grow up.

Of course ... one thing the young inherently don't have, is experience.