In most countries, there is the concept of adulthood, which brings with it several rights and responsibilities. In many countries like the Commonwealth nations, it is 18. Is there any scientific basis to choosing that particular age?
closed as not a real question by Larian LeQuella♦ Apr 7 at 12:47
It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.
(I note with a wry smile that you asked for scientific basis while giving it a "Law" tag. While not mutually exclusive, laws are made by politicians and legislators, and rarely linked to science.)
Before citing a scientist on brain development maturity, have you ever noticed that many jurisdictions will let you drive at age 16, while rental car agencies will seldom rent cars to those of that age?
(Think about what goes into renting a car: credit cards, trip planning, and decision making, to name a few. And what goes into driving itself: impulse control, attention, and more decision making. Now think about handing your keys over to a sixteen-year-old versus a twenty-five-year-old.)
Much brain research has described the integration of the prefrontal cortex with the rest of the brain. The integration does not usually finish until 10 years after puberty, or around 25 years of age. (The human frontal lobes: functions and disorders by Bruce L. Miller and Jeffrey L. Cummings, p. 577)
They cite Joaquin Fuster (2002):
(DPFC is an abbreviation for Dorsal PreFrontal Cortex.)
I do not think there is a scientific basis for how governing bodies set the age of adulthood. Is a person endowed with a certain wisdom on his 18th or 21st birthday? You probably know of 30-year-olds who should not been endowed with the rights to sign contracts, to marry, to drink alcohol, to drive, to drink-and-drive, and so on.
The de jure standard seems to be a tradeoff between giving young persons responsibilities and rights and protecting the rest of society from the exercising of those rights.
It is a totally arbitrary distinction made for economic reasons. In most western countries, secondary education is complete by the time someone reaches the age of 18, and thus are considered a member of the workforce.
First of all, here is a link to 2 people's answers, which enlightened me on the matter.
As far as I know, the age of 18 has been chosen in many countries just as an average of ages on which people showed a mature behavior. It's an age at which many people are fully grown, have a free choice of education, and are enough life-experienced to be an independent being (ie don't need the protective arms of the parents).
This question is based on a false premise.
That is a big over-simplification. There is not a single age at which children are considered adults, even in Commonwealth countries.
Consider, for example, the age at which you are:
It is clear that the choice of 18 years for some jurisdictions for some limits is a cultural, not scientific, decision.
The UN convention defines childhood as goes up to 18: http://www.unicef.org/crc/index_30229.html
Why this is is perhaps the thrust of your question.
But that it is means that it would be very hard to shift the value from 18. It's locked into International Law and will persist until genetic engineering has created adults aged, say, six, that are required for military duty.