Can lack of correlation disprove causation

[Mab6q]

I have a question about correlation and causation on the LSAT. I understand from my studies that while evidence of correlation can strengthen or weaken a claim of causation, it can never prove it. However, does lack of correlation essentially disprove a causation claim?

For example, If I say that I just had a taco and i got sick --> the taco made me sick.

That would be invalid. If we added that everyday for an entire week I had a taco and got sick, that would provide more support but it still would not prove my causation claim.

By the same token, if I had a taco and didn't get sick, that would weaken my causation claim for sure, but would it be enough to disprove it altogether. If a causal relationship means that the cause will always guarantee the effect, and if in one instance it dosent, would that completely disprove that causal claim in itself????

Thanks for the help.

[tommywallach]

Hey Mab,

It's always possible for there to be an exception to a rule, but there has to be a reason. For example, gluten causes illness in gluten-averse people, but not normal people. So knowing that some folks didn't get sick when they ate gluten wouldn't necessarily disprove the fact that gluten causes illness. However, I think you're overthinking this. The overall point you're making is that if there's no correlation, there probably isn't causation, which is OF COURSE true. The issue is always tested the other (more interesting way), because it's obvious that if two things aren't correlated, there's no cause at play.

-t