In my book Scientifically Thinking (Chapter 9), I explain the different kinds of cause and effect. Almost everything that happens has more than one cause.
Consider the example of hierarchical causation. An example of this is AIDS. If an AIDS victim dies of pneumocystis pneumonia, then you could say he was killed by the Pneumocystis carinii germ. But the reason the germ got a chance to spread was the depletion of the immune system, caused by HIV. The hierarchy of causation is, therefore, HIV—immune depletion—Pneumocystis. You cannot say “HIV does not cause pneumocystis pneumonia; Pneumocystis does.” The simple fact is that they both do, in a hierarchical fashion.
A very real example of people using hierarchical causation to mislead public opinion regards gun laws. I have heard “gun rights” people say that “Guns don’t kill people; people kill people.” The simple fact is that people use guns to kill people. It is hierarchical causation. Nobody believes that guns jump up and start shooting all by themselves. It is just a deliberate argument by the gun lobby to heap ridicule upon even mild versions of gun control.
Washington Post photo
This can lead to a dangerous situation. Many people have lots of guns and are ready to use them at the slightest provocation. And the social pressures against them are dwindling. Some white separatist groups openly display their weapons, clearly wanting us to know that they are ready to use them if something happens that they do not like. During the September 29 presidential debate, Donald Trump said that white supremacist groups should “stand by.” He clearly wants them to be ready to use their guns at some unspecified time in the future.
Another kind of causation that is misused by conservative denialists is multiple causation. This is one that has been deliberately propagated by Donald Trump. Covid-19 is caused by the coronavirus. The United States has now had more than 200,000 coronavirus deaths. But Donald Trump did not believe this. He believed that anyone who died of coronavirus but had previous underlying conditions should not be counted as coronavirus deaths. If you die of coronavirus, but you are old, then you died of being old, not from the coronavirus. Or if you have diabetes, and die of coronavirus, then you died of diabetes, not of coronavirus. Read about it here [https://www.cbsnews.com/news/covid-it-affects-virutally-nobody-trump-coronavirus-rally/]. I have not heard whether, since his diagnosis and return from the hospital, he has changed his mind about this.
The simple fact is that coronavirus deaths, in fact all deaths, have multiple causation. If a diabetic dies of coronavirus, the diabetes had weakened his or her health, and the coronavirus finished him or her off. Both the virus and the diabetes caused it. By Trump’s line of reasoning, if I (a pre-diabetic over 60 years old) die of coronavirus, it is not a coronavirus death. The simple fact is that I am getting along fine right now and am not on the brink of death; if I become ill with coronavirus, this is the spark that starts the fire. It would still be a coronavirus death.
Science denialists like to claim that, in cases of multiple causation, they can choose one of the causes and ridicule the others. This is especially true of global warming denialism, the subject of the next essay.