> The hypothesis that lead exposure affects early childhood development, and that this leads to higher crime rates does lead to testable predictions ...
Yes, but not falsifiability, required for science. Okay, I see people aren't getting this, so here's a classic example. Let's say I am a doctor who believes he has found a cure for the common cold. My cure is to shake a dried gourd over the cold sufferer until he gets better. The cure might take a week, but it always works. My method is repeatable and perfectly reliable, and I've published my cure in a refereed scientific journal (there are now any number of phony refereed scientific journals). And, because (in this thought experiment) science can get along without defining theories, without falsifiability, I'm under no obligation to try to explain my cure, or consider alternative explanations for my breakthrough — I only have to describe it, just as lead in gasoline is being described as inversely correlated with crime rates in the linked article.
> Is this as strong as exposing a test population and comparing it to a control? No. But neither is it meaningless pseudo-science.
But that is exactly what it is -- meaningless pseudoscience -- on the ground that no one is crafting and then testing theories about the correlation. Until we know why A is correlated with B, until we can demonstrate a cause-effect relationship and make falsifiable predictions based on the theory, it's not science.
> But not everything worth investigating (and worth knowing) is amenable to that type of study.
Yes, I agree, science can't provide answers to questions not amenable to the scientific method (i.e. "that type of study"), and not all important questions have this property.
Yes, but not falsifiability, required for science. Okay, I see people aren't getting this, so here's a classic example. Let's say I am a doctor who believes he has found a cure for the common cold. My cure is to shake a dried gourd over the cold sufferer until he gets better. The cure might take a week, but it always works. My method is repeatable and perfectly reliable, and I've published my cure in a refereed scientific journal (there are now any number of phony refereed scientific journals). And, because (in this thought experiment) science can get along without defining theories, without falsifiability, I'm under no obligation to try to explain my cure, or consider alternative explanations for my breakthrough — I only have to describe it, just as lead in gasoline is being described as inversely correlated with crime rates in the linked article.
> Is this as strong as exposing a test population and comparing it to a control? No. But neither is it meaningless pseudo-science.
But that is exactly what it is -- meaningless pseudoscience -- on the ground that no one is crafting and then testing theories about the correlation. Until we know why A is correlated with B, until we can demonstrate a cause-effect relationship and make falsifiable predictions based on the theory, it's not science.
> But not everything worth investigating (and worth knowing) is amenable to that type of study.
Yes, I agree, science can't provide answers to questions not amenable to the scientific method (i.e. "that type of study"), and not all important questions have this property.