[Reincarnate]

Age is just a heuristic/proxy at the end of the day. A measure of reasoned correlation based on a collection of judgments/precedents/whatever/etc.

I mean, I think maturity is a pretty ambiguous term. To me, maturity implies that something has progressed to some state of fruition. One's skills can mature: You start out as a neophyte at a particular hobby and eventually become sufficiently competent. Maybe you're socially immature -- saying dumb things when you're young and eventually learning how to maintain composure and acquire the means to conduct yourself more rationally.

Of course, these are still pretty vague constructs. What's considered sufficient? Ultimately we change around laws and shit because we'd like to maximize everyone's utility, and so what's sufficient is pretty hard to measure. It's something I think you have to adjust until things improve in the relevant areas. For instance, maybe deaths by drunk drivers would decrease if you lowered the drinking age and improved education, thereby removing the "forbidden fruit" aspect and empowering people with knowledge of responsible use. As a result, you may end up with a more "mature" teenage population when it comes to alcohol even though the age limit is lower. Other things would need to change too, but I'm just trying to illustrate a general point there.

To me, maturity also implies a sort of forethought and the ability to see the consequences of one's actions. It implies an awareness of details -- a greater complexity. Instead of just blurting out whatever you think is funny, maybe you take a moment to think before you speak, assess your audience, determine if the setting is appropriate, whatever. Instead of blowing your paycheck on useless crap, maybe you think ahead, save it instead, and get yourself to a more stable place financially. Lots of possible examples.

I'm convinced that age is only a reasonable proxy in a small, finite number of situations. One of the big eye-openers I've encountered, growing up, is that so many adults have no fucking idea what they're doing (despite what I may have thought of them as a child). Many people make very immature and irresponsible decisions in a variety of situations. If the law could perfectly discriminate, some people could handle certain responsibilities at a very young age, while others would never acquire such rights until the day they die.

So age-of-consent laws are pretty much arbitrary. At some point a bunch of people figured that going below that figure was too low, or going above that limit too much was too high, etc. That's about it. The rational and empirical underpinnings evolve over time but meh.