# Why is 18 considered when you become an adult? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [November 9, 2013, 2:21pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507 "2013-11-09T14:21:23Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![James\_Toothpaste](https://avatars.discourse-cdn.com/v4/letter/j/e56c9b/32.png) [@James\_Toothpaste](https://boards.straightdope.com/u/James_Toothpaste)\ **Post date:** [November 9, 2013, 2:21pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/1 "2013-11-09T14:21:23Z")
It seems so random. 13 or 20 should be the age. ---
**Author:** ![ticker](https://avatars.discourse-cdn.com/v4/letter/t/d07c76/32.png) [@ticker](https://boards.straightdope.com/u/ticker)\ **Post date:** [November 9, 2013, 2:24pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/2 "2013-11-09T14:24:51Z")
Not random at all, maybe a bit arbitrary. ---
**Author:** ![lawbuff](https://avatars.discourse-cdn.com/v4/letter/l/13edae/32.png) [@lawbuff](https://boards.straightdope.com/u/lawbuff)\ **Post date:** [November 9, 2013, 2:27pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/3 "2013-11-09T14:27:01Z")
That is the age MOST graduate from High School. ---
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [November 9, 2013, 2:27pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/4 "2013-11-09T14:27:11Z")
Why is 18 “random” but 13 or 20 makes sense?! ---
**Author:** ![rsat3acr](https://avatars.discourse-cdn.com/v4/letter/r/a3d4f5/32.png) [@rsat3acr](https://boards.straightdope.com/u/rsat3acr)\ **Post date:** [November 9, 2013, 2:53pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/5 "2013-11-09T14:53:07Z")
during the Vietnam war there were complaints that 18 year olds could be drafted but couldn’t vote and the reasining was that you should be able to vote if you can be sent to war. Voting age changed from 21 to 18. Of course one is just as arbitrary as the other. ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [November 9, 2013, 3:09pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/6 "2013-11-09T15:09:10Z")
In the UK it’s not simple: 14 + You can get a part time job, for a maximum of two hours on a school day, working sometime between 7.00am and 8.00am and 5.00pm and 7.00pm. If convicted of a serious criminal offence (in a Youth Court), You can be held in secure accommodation for no more than 24 months. You could also get a fine for a maximum of £1,000. Wearing a seatbelt is considered your own personal responsibility, so buckle up. 16+ You have the right to give consent to medical, dental and surgical treatment. This includes contraceptive advice and treatment. You can leave school You can have sex, gay or straight, so long as your partner is also 16+ You can claim benefit and obtain a National Insurance number. You can drink a beer, wine, or cider with a meal in a pub or restaurant if you are with an adult. You can ride a moped with a max engine power of 50cc (and a provisional licence). You can work as a street trader and/or sell scrap metal. You can work full time if you’ve chosen to leave school (but not in a bar or a betting shop). You can join the armed forces (so long as that’s OK with your parent/s or carer). You can move out of the family home with your parents’ permission.(If you’re under 17 then Social Services may apply for a Care Order). You can rent accommodation, but a guarantor is required until you’re 18 (this is an adult who can be responsible for you). You must pay for prescription charges (unless you’re pregnant, on income support or in full-time education). Laws in Wales differ though. You can order your own passport. You can play the National Lottery. You can buy premium bonds. You can fly a glider. You can get married (with parental consent). And you can buy liquor chocolates. At last. 17+ You can drive most types of vehicles if you pass your driving test. You can apply for a private pilot’s licence for a plane, helicopter, gyroplane, hot air balloon and airship. You can be interviewed by the police without an adult present, given a reprimand or a warning. You can become a blood donor. You can leave your body for medical study. 18+ You can vote in local and general elections. You can stand for election as a Member of Parliament, local councillor or Mayor. You can serve on a jury, or be tried in a magistrates court and go to jail if you’re found guilty of a criminal offence. If you were adopted you can see your original birth certificate (and have your name added to the Adoption Contact Register). You can make a will. You can sign and enter ino a legal contract. You can get married without parental permission. You can view, rent or buy an 18 rated film or pornographic material that does not contravene UK obscenity laws. You can buy fireworks. You can place a bet in a betting shop/casino. You can buy cigarettes, rolling tobacco and cigarette papers. You can open your own bank account. You can buy an alcoholic drink in a pub or a bar. You can pawn stuff in a pawn shop. You can have a tattoo. You can drive lorries weighing up to 7.5 tonnes, with a trailer attached. You can buy knives and unencased razor blades (the common ‘safety’ razors for shaving can be bought at any age). 21+ You can apply to adopt a child. You can supervise a learner driver (so long as you’ve held a driving licence for the same type of vehicle for three years). You can apply for a range of licences that would allow you to fly commercial transport aeroplanes, helicopters, gyroplanes and airships. You can drive lorries over 7.5 tonnes with a trailer (with the appropriate licence), as well as buses and road rollers. This is not a fully comprehensive list. ---
**Author:** ![Uniqueorn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uniqueorn/32/2807_2.png) [@Uniqueorn](https://boards.straightdope.com/u/Uniqueorn)\ **Post date:** [November 9, 2013, 3:23pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/7 "2013-11-09T15:23:50Z")
Allegedly, the frontal lobe matures in humans in their early 20s, and as the frontal lobe seems to be the part of the brain responsible for rational thinking, the age of maturity should maybe be raised by a few years. > **[Frontal lobe](https://en.wikipedia.org/wiki/Frontal_lobe)** > > The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove between tissues called the central sulcus and from the temporal lobe by a deeper groove called the lateral sulcus (Sylvian fissure). The most anterior rounded part of the frontal lobe (though not well-defined) is known as the frontal pole, one of the three pole... ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 9, 2013, 3:46pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/8 "2013-11-09T15:46:27Z")
> [@](#): > > In the UK it’s not simple: In the US it’s even less simple, since we similarly have a range of different ages at which one is considered “adult” for various purposes, but almost all of those ages vary from state to state. ---
**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\ **Post date:** [November 9, 2013, 4:07pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/9 "2013-11-09T16:07:51Z")
The US originally adopted 21 from British common law; it was supposedly derived from the age a squire was allowed to be a knight (note that it was not true across the board: King Richard II was crowned king at age 10). Over the years, the various states have adjusted that for various reasons. The drinking age was usually 18 back in the 60s; it’s now 21 just about everywhere. Voting age went the other direction: from 21 to 18. The reasons for the age changes are complicated and often different in each state. ---
**Author:** ![Darth\_Panda](https://avatars.discourse-cdn.com/v4/letter/d/ee7513/32.png) [@Darth\_Panda](https://boards.straightdope.com/u/Darth_Panda)\ **Post date:** [November 9, 2013, 4:10pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/10 "2013-11-09T16:10:26Z")
It would be better if the age was actually random. ---
**Author:** ![aceplace57](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aceplace57/32/3500_2.png) [@aceplace57](https://boards.straightdope.com/u/aceplace57)\ **Post date:** [November 9, 2013, 4:21pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/11 "2013-11-09T16:21:55Z")
It’s changed in modern times. It was common for boys and girls to leave school by the 5th or 6th grade. They were considered men and working full time by 15. My granddad had a 7th grade education. He left home to work in the oil fields at 16. He was 20 when he married my 14 year old grandmother. She only had a 4th grade education. She left school to help raise her sisters. She had been running a household, cleaning and cooking for several years before marrying. This wasn’t unusual at all even in the 1920’s. Treating someone like a kid until they are 18 is a very modern idea. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [November 9, 2013, 4:36pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/12 "2013-11-09T16:36:51Z")
This might be better in IMHO. Colibri General Questions Moderator ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [November 9, 2013, 4:53pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/13 "2013-11-09T16:53:11Z")
> [@aceplace57](#): > > my 14 year old grandmother Now there’s a phrase you don’t see every day! ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [November 9, 2013, 5:29pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/14 "2013-11-09T17:29:39Z")
Tradition, and we are too lazy to give every kid a “maturity” test. Hellfire, some of probably shouldn’t be considered reasonable adults even at age fifty. ---
**Author:** ![handsomeharry](https://avatars.discourse-cdn.com/v4/letter/h/e9c0ed/32.png) [@handsomeharry](https://boards.straightdope.com/u/handsomeharry)\ **Post date:** [November 10, 2013, 5:59am UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/15 "2013-11-10T05:59:32Z")
> [@rsat3acr](#): > > during the Vietnam war there were complaints that 18 year olds could be drafted but couldn’t vote and the reasining was that you should be able to vote if you can be sent to war. I think that much of the debate was rather, that you can be \*drafted \*and sent to war, rather than just sent to war, without the right to vote. ---
**Author:** ![Siam\_Sam](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@Siam\_Sam](https://boards.straightdope.com/u/Siam_Sam)\ **Post date:** [November 10, 2013, 6:53am UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/16 "2013-11-10T06:53:56Z")
> [@aceplace57](#): > > my 14 year old grandmother. > [@Thudlow\_Boink](#): > > Now there’s a phrase you don’t see every day! Not outside Tennessee, at least. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [November 10, 2013, 7:21am UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/17 "2013-11-10T07:21:50Z")
> [@DrFidelius](#): > > Tradition, and we are too lazy to give every kid a “maturity” test. More like, we don’t _actually have_ a “maturity test” to give them in the first place. ---
**Author:** ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)\ **Post date:** [November 10, 2013, 7:54am UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/18 "2013-11-10T07:54:49Z")
Because in most places the younger ages have been shotgunned by [the age of consent.](http://en.wikipedia.org/wiki/Ages_of_consent_in_North_America) ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [November 10, 2013, 1:43pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/19 "2013-11-10T13:43:13Z")
> [@Der\_Trihs](#): > > More like, we don’t _actually have_ a “maturity test” to give them in the first place. Details. The government could have cobbled up a “maturity test” if they felt the need, similar in the way that “intelligence tests” were used for years to exclude certain classes of immigrants. ---
**Author:** ![James\_Toothpaste](https://avatars.discourse-cdn.com/v4/letter/j/e56c9b/32.png) [@James\_Toothpaste](https://boards.straightdope.com/u/James_Toothpaste)\ **Post date:** [November 10, 2013, 3:03pm UTC](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507/20 "2013-11-10T15:03:22Z")
> [@DCnDC](#): > > Why is 18 “random” but 13 or 20 makes sense?! Because 13 is the first teen age, and 20 is a solid decade number. [Next page](https://boards.straightdope.com/t/why-is-18-considered-when-you-become-an-adult/673507.md?page=2)