Folks, as a scientist I live and breathe the analysis of data. And one of the cardinal rules of science and statistics is that correlation does not imply causation–in other words, we can only ever say that y and z are related, but not that one causes the other. There is always the possibility of confounding and lurking variables that could have unduly influenced results. And there are various mathematical models to ascertain the degree to which y and z are related to each other. The benefit of using this logic is that it prevents one from incorrectly pointing the finger at something as the cause of another thing (or conversely claiming that one thing doesn’t cause another).
The danger of this, on the other hand, is that sometimes it prevents people from pointing a finger at something at all. I’ve noticed that this has become a common rhetorical strategy in arguments and debates. And I’ll freely admit that I’ve used it in the past. When someone pulls out the “correlation vs causation” card it’s a surefire way to trump someone’s argument. After all, how does one address what amount to essentially invisible, hypothetical variables? It’s impossible to do so, obviously, so the argument ends with, “Well, correlation vs causation, so I guess it’s really a wash.”
The problem is that in real life there are no washes or cop outs. Practically speaking, yes, everything does have a cause. Perhaps sometimes there are multiple factors influencing the outcome of something, but all of those factors behave according to the laws of the universe, and therefore act in concert in a predictable, measurable way–even if we human beings cannot as of yet predict or measure those influences. I can’t help but feel that the “correlation vs causation” device completely undermines the scientific process.
When people use correlation vs causation outside of a scientific context, what they’re really saying boils down to,”Well it’s impossible to know for sure, so I win.” I mean, technically speaking, someone could use the correlation vs causation device to successfully argue against the statement: “If I throw a ball into the air then gravity will pull it back down to the earth.” In other words, it’s not a very practical argument. The logic of using the scientific principle as a rhetorical device is baffling. If someone wants to make the correlation vs causation point in an argument, then they’ve not only defeated their opponent’s argument, but they’ve simultaneously defeated every argument, including their own.
Blindly attacking the principles of certainty and uncertainty doesn’t make any sense because technically, using the scientific definition, everything has a degree of certainty and uncertainty associated with it. So what’s the point of using the argument at all? Cleary, z happened. We know that. We saw it. We have data confirming it. There’s no arguing whether or not an event happened. And, as we know, things just don’t happen by themselves. For every cause their is an effect and vice versa. There’s a rhetorical disconnect between knowing that something happened and then using an argument to say that it’s impossible to determine what caused said event.
It makes much more sense to attack probability than it does to attack correlation and causation. Rather than make a blanket statement about how it’s impossible to ever prove whether or not one thing causes another, it makes much more sense to make an argument about which things are more likely to have caused something. Because, as I mentioned in the previous paragraph, when something happens, there is obviously a cause. And in most cases we have evidence–data–about an event. And, as I mentioned at the beginning of this piece, there are mathematical models out there to determine the degree to which one thing is associated with something else. So doesn’t it make more sense to take all of the data, determine what the possible causes are, and then run each one through the math to determine which explanations are most probable?
Because in reality it makes no sense to declare, “Well, it’s impossible to ever be certain about anything, which makes all arguments invalid, which makes your argument invalid.” It makes much more sense to say, “Well, looking at the data, my argument is more likely than yours.” The second statement still leaves room for uncertainty, and it still leaves room for further investigation and discovery, while acknowledging that something had to have caused whatever you’re debating about.