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===[[Correlation]] and [[causation]]===
===[[Correlation]] and [[causation]]===
Now it is true that [[correlation]] doesn’t imply [[causation]], but it doesn’t rule it out either.  And it is certainly true that a ''lack'' of correlation ''does'' imply a ''lack'' of [[causation]].
Now it is true that [[correlation]] doesn’t imply [[causation]], but it doesn’t rule it out either.  And it is easy to infer from a ''lack'' of correlation that there is no [[causation]]. But hold your horses.


[[All other things being equal]], a [[correlation]] is more likely to evidence a [[causation]] than a ''lack'' of correlation, right? This is one of those logical canards, as Monty Python put it, “[[universal affirmative]]s can only be partially converted: all of Alma Cogan is dead, but only some of the class of dead people are Alma Cogan.”
[[All other things being equal]], a [[correlation]] is more likely to evidence a [[causation]] than a ''lack'' of correlation”, is one of those logical canards. As Monty Python put it, “[[universal affirmative]]s can only be partially converted: all of Alma Cogan is dead, but only some of the class of dead people are Alma Cogan.”


So here’s the thing, and I am straining to avoid distracting myself onto my pet subjects of transcendent truth and causal skepticism, so bear with me:
So here’s the thing, and I am straining to avoid distracting myself onto my pet subjects of transcendent truth and causal skepticism, so bear with me:


Even if you accept some [[reductionism|objectivist ]] model where, whether we can know it or not, there ''is'' a true, unique, cause for every effect — and down that rabbit hole are a bunch of consequences you really wouldn’t like, but let’s say — it follows that an event must have but ''one'' cause (or consistent matrix of causes) to the absolute exclusion of any other explanation. There cannot be alternative, mutually exclusive, causal explanations of the same event, for that would imply ghastly [[relativism]]<ref>Not ghastly.</ref>
Even if you accept some [[reductionism|objectivist ]] model where, whether we can know it or not, there ''is'' a true, unique, single cause for every effect — and down that rabbit hole are a bunch of consequences you really wouldn’t like, but let’s say — it follows that an event must have but ''one'' cause (or consistent matrix of causes) to the absolute exclusion of any other explanation. There cannot be alternative, mutually exclusive, causal explanations of the same event, for that would imply ghastly [[relativism]]<ref>Not ghastly.</ref>


That is to say, for every single ''true'' cause, there are multiple [[spurious correlation]]s — events that serendipitously ''seem'', by their statistical regularity, to have causal significance to each other but, in transcendent fact, don’t.  
That is to say, for every single ''true''” correlation, there are multiple ''spurious'' correlations — events that serendipitously ''seem'', by their statistical regularity, to have causal significance to each other but, in transcendent fact, don’t.  


How many is “multiple”? ''Depends on how much data, and how much imagination, you’ve got''. Seeing as [[the portion of all data we have collected is nil| portion of all data we have collected is necessarily nil]], the best answer is that ''there are infinite [[spurious correlation]]s and only one ''true ''correlation between a cause and its effect''. The likelihood, without better evidence,<ref>You are right. This qualification is doing ''a lot'' of work.</ref> that a given correlation is the true one is therefore 1/∞, or ''zero''.
How many is “multiple”? ''Depends on how much data, and how much imagination, you’ve got''. Seeing as [[the portion of all data we have collected is nil| portion of all data we have collected is necessarily nil]], the best answer is that ''there are infinite [[spurious correlation]]s and only one ''true ''correlation between a cause and its effect''. The likelihood, without better evidence,<ref>You are right. This qualification is doing ''a lot'' of work.</ref> that a given correlation is the true one is therefore 1/∞, or ''zero''.


So it is true to say a lack of any correlation may not increase the likelihood of events being causally related, ''but nor does the presence of one''. Especially seeing as there may be some data, as yet uncollected or [[narrative|unnarratised]], that could explain how apparently uncorrelated events are, in fact, causally related.
So it is true to say a lack of any correlation may not increase the likelihood of events being causally related, ''but nor, without other evidence, does the presence of one''. Especially seeing as there may be some data, as yet uncollected or [[narrative|unnarratised]], that could explain how apparently uncorrelated events are, in fact, causally related.


Where does this leave us? Well, correlation, in the absence of better evidence of causation, is ''meaningless''. It dodges the hard question, which is, “what possible ''better evidence'' of true causation — a “necesary connexion” between cause and effect — ''could there be''?”
Where does this leave us? Well, correlation, in the absence of better evidence of causation, is ''meaningless''.  


This is not a new conundrum. It was first posed by {{author|David Hume}}, in 1739 — “necesary connexion” is his phrase — and he answered it in the negative. There is no evidence of causation.
Glomming on to a satisfying correlation dodges the hard question, which is, “what possible ''better evidence'' of true causation — a “necesary connexion” between cause and effect — ''could there be''?”
 
This is not a new conundrum. It was first posed by {{author|David Hume}}, in 1739 — “necesary connexion” is his phrase — and he answered it in the negative. There is no better evidence of causation.


But, fortunately for the interests of narrow-minded righteousness and [[determinism]], Hume allegedly once met someone who was racist, so we can entirely ignore him and the quarter of a millennium of epistemology that he spurred. Plus, he was a Scot.
But, fortunately for the interests of narrow-minded righteousness and [[determinism]], Hume allegedly once met someone who was racist, so we can entirely ignore him and the quarter of a millennium of epistemology that he spurred. Plus, he was a Scot.