Mistaking the Relevance of Proximate Causation

Mistaking the Relevance of Proximate Causation

David Kyle Johnson

Guns don’t kill people; people kill people. — NRA slogan

A cause does not become irrelevant because another cause preceded it. Nor does identifying the immediate cause settle every question about responsibility. This fallacy involves mistaking what an immediate cause does, or does not, establish.

When it comes to causation, things are hardly ever as simple as A caused B. Consider this question: “What caused these words to appear on this page?”

We might say that those words were caused to appear by my decision to write those words, but that decision would not have amounted to much without its being followed by an entire series of other causally relevant events. That decision caused my fingers to move, which caused the keys of my keyboard to move, which caused the words to appear in my text document (and on my screen). I then sent that document to the editors, who added it to a larger document, which was eventually printed by a large machine onto these pages. If any of these steps had been missing, those words would not have appeared on this page. Causal stories are usually long and complicated and involve a chain of events.

To keep things straight, it will be helpful to clarify some terminology. Let’s call the event that starts off the chain the “ultimate cause,” the subsequent events the “intermediate causes,” and the event that plays the most immediate causal role in bringing about the event the “proximate cause” (because it is closest in proximity to the event in question). This use differs from the legal definition of “proximate cause” (see Rottenstein 2015). So, in the example above, the words being printed is the proximate cause.

Now, generally speaking, it’s true that proximate causes wouldn’t exist (or couldn’t do much) without their ultimate cause. But that doesn’t mean that the proximate cause didn’t play an important (or even necessary) role in bringing about the event in question. For example, while it is true that my decision to type the above sentence was the ultimate cause of those words appearing on the printed page, they could never have done so without the printing press that printed them. And this is how one can mistake the relevance of proximate causation. One mistakes the relevance of proximate causation when one thinks the fact that something is a proximate cause makes it irrelevant to the story of how the event in question happened (or whether or not it would have happened).

So take the NRA slogan “Guns don’t kill people; people kill people.” The implied conclusion is that guns are not to blame for the acts of violence (such as a mass shooting) in which they are used because a person is the ultimate cause of the violence (not the gun). Without a person to wield it, a gun can do no harm.

But, while this is true, it does not follow that guns do not play an important causal role in things like mass shootings – and so it doesn’t follow that regulating guns wouldn’t do anything to reduce the frequency of mass shootings. Guns can make murdering people en masse easier. That causal role matters to the debate, but the effects of a particular regulation require evidence beyond this point alone.

The fallaciousness of this argument becomes obvious when we exaggerate it. Suppose it was legal to own a military‐style tank and then someone took the tank, attacked a building, took it down, and killed all those inside. Suppose that when people then called for owning a tank to be outlawed, someone pointed out that, without an operator, a tank is perfectly harmless. “Tanks don’t kill people; people do.” Of course this is true, but that doesn’t mean that the tank didn’t play an important causal role in bringing the building down – and it doesn’t mean that outlawing tanks would do nothing to prevent such tragedies. Although they are proximate causes, they do make bringing down entire buildings much easier; making tanks harder to attain could reduce tank‐related deaths.

Of course, it’s undeniable that tanks are not guns and that there are other arguments and factors to consider regarding whether and how much (and which) guns should be regulated. But it’s equally undeniable that pointing out that guns are “merely proximate causes” is irrelevant to that debate. I wouldn’t say, as philosopher William Harwood (2015) did, that anyone who makes such an argument is an anti‐American bigot (although he makes a good point about the argument itself). I would say, however, that the argument doesn’t deserve a place in a rational debate about gun regulations.

Mistaking the relevance of proximate causation can also “go the other way.” That is, one can overinflate the importance of something being a proximate cause (instead of finding it irrelevant). This is often done by those looking to avoid responsibility for their actions. Suppose you have a rich uncle with cancer in the hospital on life support and that you pull the plug so as to get the inheritance you were promised. Could you rightfully claim that you were not responsible for his death by pointing out, “Hey, I didn’t kill him – the cancer did”? Of course not; cancer contributed to his condition, but removing life support also played an important causal role in his death. Yet this line of reasoning appears quite often in daily life, usually from those wanting to avoid responsibility for their actions. For example, my students often want to blame me for their bad grades – since I am the one who assigned them their grade – instead of blaming themselves, their lack of studying, or their inability to write a well‐argued paper.

But, of course, things are not always straightforward. Who’s to blame for the execution of a criminal on death row? The criminal himself, those who enacted capital punishment laws, or those who refuse to repeal them? Who is more responsible for the financial crash of 2008 – those who deregulated the financial sector or those in the financial sector who took advantage of its deregulation? Who bears more responsibility for the presence of ISIS in Iraq – the members of ISIS itself, President Obama, whose removal of troops left a power vacuum for them to fill, or George W. Bush, whose invasion of Iraq made a power vacuum in Iraq inevitable? Matters of causation are never simple. And sometimes whether something is a proximate cause is relevant to the issue at hand. But we must be careful to make sure that we don’t mistake its relevance.