I don't know how many people have both the expertise and interest (I know I lack the former) to discuss this, but I found this proposed explanation for the internationally observed reduction in violent crime intriguing. The theory goes that the elimination of lead in petrol and household products closely corresponds to reduced crime everywhere you look.
The data is irrefutable - violence of all kinds is at an all-time low. I think to pick out a single cause (like lead) is reductionist. I think that all sorts of small changes have contributed, from CCTV and better policing to better treatment of learning disabilities and behavioural disorders. There's a good argument that access to abortion has helped reduce crime, by reducing the number of unwanted babies that grow up to be delinquents.
It's a slightly facile argument, but I'd make the case that crime prevention is just another form of technological development. Design a better car alarm and you reduce theft, design a better cab rank and you get fewer punch-ups at chucking-out time. You solve lots of little problems that aggregate into a huge change.
> There's a good argument that access to abortion has helped reduce crime, by reducing the number of unwanted babies that grow up to be delinquents.
You probably already know this, but that one is a well-known phenomenon which was nicely covered in the rather famous book Freakonomics.
Regarding lead, the correlation is undeniable (across various disparate territories and even when taking other factors into account) but that doesn't mean there's necessarily any causation. Unlike with abortion there isn't any obvious reasoning why its reduction should have caused such a dramatic reduction in crime beyond some shaky "leak is a neurotoxin that makes us all act bad" theory.
The lead argument is based on the straightforward correlation between IQ and criminality - people with lower IQs are more likely to commit crime, lead toxicity lowers IQ, therefore lead toxicity may cause crime. It's a fairly loose chain of causation, but perfectly plausible on face value.
>people with lower IQs are more likely to commit crime, lead toxicity lowers IQ, therefore lead toxicity may cause crime.
IQ is not a proper measure of how intelligent you can potentially be but rather a measure of how educated you are, which means that people with lower IQ tend to be from impoverished backgrounds. The same 95 IQ chav could have been a 120 if he had been born into a richer family. So the argument now goes:
>People from poor and anti-educational backgrounds tend to have a lower IQ, people with lower IQs are more likely to commit crime, lead toxicity lowers IQ, therefore lead toxicity may cause crime.
Which doesn't really make too much sense. In fact I'd argue that lead is irrelevant to crime, and it's a matter of a good solid education for all.
>IQ is not a proper measure of how intelligent you can potentially be but rather a measure of how educated you are
This is arguably untrue. Correctly managed IQ tests compose two papers (really big puzzle books, essentially), one of which is variety of logical and numerical problems, the other of shape and pattern-based problems (to measure basic cognition and offset such bias). As long as the subject is capable of reading and completing these, education should not be a limit on achieving a respectable score.
>People from poor and anti-educational backgrounds tend to have a lower IQ, people with lower IQs are more likely to commit crime, lead toxicity lowers IQ, therefore lead toxicity may cause crime.
>Which doesn't really make too much sense. In fact I'd argue that lead is irrelevant to crime, and it's a matter of a good solid education for all.
Wealth is linked to diet and nutrition, which in turn is linked to intelligence.
It is also arguable that people who would score low in both logical and cognitive tests are treated differently by society, have fewer opportunities (or are oblivious to those that exist), and perceive the world accordingly. They are also more likely to be caught having committed an offence. If exposure to lead reduces intelligence by a significant degree then a correlation may exist.
>IQ is not a proper measure of how intelligent you can potentially be but rather a measure of how educated you are
That's not true in the least, and I'd suggest you go and find out what an IQ test actually is because you appear to be severely misinformed. As >>3609 describes, a correctly composed IQ test assesses abstract reasoning and requires no prior knowledge.
While it is true that environmental influences can affect IQ, the effect is relatively weak, as demonstrated in numerous twins studies over the years. Education is far less significant than adequate nutrition and good parental interaction. Events like toxic exposure and head injury can drastically reduce IQ. The predominant influence on IQ is heredity.
Your second statement is clearly a nonsense, predisposed upon the fallacious idea that IQ is purely a measure of educational attainment.
