Why is age 18 used to demarcate children from adults?

I guess I don’t know where you’re from, but in my state a 17 year should already have their licence. Also, depending on the crime, a person under 18 could very well be tried as an adult. As for voting, since you’re out of the ‘mandatory’ school system, I suppose they’re figuring that you’ll know all you need to in order to make a judgement call on that. You can have sex at whatever age, you just can’t be 18 with someone who isn’t yet. And alcoholic beverages can only be served to people who are 21+.

…I have no idea about the marriage part…

It’s arbitrary. It used to be you couldn’t vote until 21, but when they were sending 18 year-olds to serve in WWII (guess they needed the soldiers!) they had to let them vote as well. It changes with the times—there’s no natural or even particularly traditional reason for it.

And even now the ages at which “adult” things can be done varies. The age of consent in US states varies between 16 as does the legal driving age. In California, the legal driving age is 16. (Not to mention that driving breaks down into further gradations like getting a permit—which can be done at 15 in California—versus a license versus being able to rent a car.) And the drinking age is way above, at 21 for all states (but again—wasn’t always that way… used to vary as well until the federal government threatened the states into changing it).

Well its different everywhere, 21 to drink in the states and 16 in a lot of europe.

Social convention.

I feel there is good reason to have restrictions for younger people, on certain actions.

For example:
When it comes to driving… younger drivers, regardless of their driving experience, cause more traffic accidents. That doesn’t only affect themselves, but also the other participants in traffic.

Young people’s brains go through enormous change, especially in adolescence, and alcohol has a negative impact on that development. 21 is a safer age than 18, or 16 or even younger.

Younger people lack some experience in life and are not always the best to judge, therefore restricting their voting rights doesn’t seem too unreasonable. Whether the age should be 16, 18 or 21, I don’t know. I personally feel 18 is fine.

In any case… one grows out of this dilemma before one knows it.

Largely because it’s easier to set some arbitrary age at which you are legally an “adult” than it is to test everyone to see if they’ve matured sufficiently to be considered one.

I am curious to know where the 16, 18 and 21 figures originated from. GQ!

Since there is no “magic age” at which all ( or even MOST ) teenagers become adults, I rather suspect someone pulled them out of… well, thin air! Heh!

It is just a matter on social resolution. In different cultures the age of maturity is much different. Sometimes it is puberty.

It makes sense though.

Since most people tend to live up ( or DOWN! ) to the expectations of those around them, having the onset of puberty as the legal age of adulthood would have enormous impact on the behavior of teenagers. We can see some of this in many Jewish communities, where Bar and Bat Mitzvas are held on the child’s 12th birthday.

As has been said, the basic answer is that coming of age at 18 is a social convention. As adults are typically understood to have full rights, you get everything you lacked previously all at once. But the numbers then get shifted around in reaction to specific circumstances.

The driving age, for instance, shifts up and down based on society-relative factors such as the importance of cars, whether or not teenagers are expected to work, the availability of parents to drive their children around, and the statistical distribution of serious accidents among age groups (though this last one is more likely to spark debate than long-term change).

It’s somewhat arbitrary, but in the U.S., at least, most people graduate from high school at age 18. You still have to be 21 to purchase alcoholic beverages, but it hasn’t always been so – I could drink at 18 during the Vietnam war. There are also different definitions of adulthood depending on the circumstances. In most states, you will be tried as an adult at age 16 for most crimes. This raises a lot of social and legal issues, e.g., are you really getting the equal protection of the law if you can be tried as an adult at 16, but you can’t enter into a contract until you’re 18? How do you hire a lawyer?

As if adolescence didn’t suck enough…

Probably because, at the age of 18, you’ve graduated high school and get thrown into the “real world”, so you’re considered to be more of an “adult”.

@Arbornaut I didn’t know that. Bye guys. ~

@CaptainHarley Bar Mitzvah for boys age 13, Bat Mitzvah for girls age 12

First off, let me copy something from one of the gaming forums I frequent. (Forgive the spelling, but that is how it was posted.)

“The age of consent has steadily increased in industrial societies in so small part due to the social effects of the indistrial revolution. The need for more education combined with more labor saving devices resulted in people spending more and more time in school. It began as an artifical social construct called ‘childhood’, which justified mandatory government provided schooling. As educational requirement increased newer age classess were invinted so that this mandatory schooling could be extended. Now, with college education being almost necessary for survival a 22 year old is considered a child in some respects. ”

Now, I have heard it said that 26 is the new 18 for that exact reason. It used to be that most people stopped their education at 18; about the time most people graduate high school. Before high school was mandatory, 18 wasn’t nearly the magical number it is now.

Have you noticed that it is only that way here? In Europe, they let people we Americans would consider kids do far more, like drink, drive, and screw (though not at the same time). And in less industrialized nations, the rules are even laxer. It is only here in the epitome of First-world nations, the pinnacle of industrial might, that we are uptight about age.

@jerv This list does not agree with what you have presented

@YARNLADY Thank you for fact-checking. I am aware of the law, how relatively recent it is, and the difference between de jure and de facto. That last one is especially important in some contexts.

A line must be drawn somewhere for the purpose of assigning liability after the fact.

Eighteen seems just about as arbitrary as any other number.

Social changes have made the moment of adulthood a vague thing. Adolescence was more of an invention rather than a discovery.

I’m a bit annoyed that one can be forced to risk death defending our nation’s Constitution yet can’t drink a beer.

As said before, it some arbitrary number snatched from imagination, then justified by that is when graduation or some other event took place. Another cram it through logic is you can’t test when a person is mature enough to be an adult, so you have to have some artificial number, (which they then seek to find loopholes in). You don’t need any artificial number if you go by biology and ditch ideology; when a male was able to sire a child and a female was able to birth a child, are adults, be it very young adults. If teenagers brains are too scattered to make wise decisions on entering contracts, voting, etc. it certainly has to be much wiser allowing them to boink like bunnies with no checks or safeguards other than handing them boxes of rubbers after gym class. The ideal of keeping young adults children longer is clearly ideology because people want to be parents longer than nature ever intended. As pointed out, there is a flaw in that thinking, where a person has to be 18 to vote, consent to sex, or enter into contracts in most places, if the same person shot up 8 quickie marts killing 2 of the clerks, NOW they are worthy to be treated as adults before 18. Going to the amusement park, riding public transit, Amtrek, going to the movies, etc. they were always regarded as adults when they became 12 years of age; I guess money can get you seen as a de facto adult with no teeth or real power behind the moniker. Making the legal age 18 is more about societal control than anything else.

Based on the Hebrew word Chai (Het Yud) – Hebrew characters have numeric values and the value of Chet + Yud = 18. Chai is translated as LIFE.

So true life begins at 18