© Roger M Tagg 2009 revised 2011-2
The essay is about whether we can ever really claim that something, or somebody is the cause of some state of affairs. Saying that "A causes B" or "A caused B" is usually a case of using the word cause very loosely, and is a feature of much everyday bullshit. One recent examples was an Australian opposition claim that "the (current) Government caused the economic downturn" - presumably implying their incompetence. Never mind other factors, like sub-prime mortgages in the USA, or the GFC (Global Financial Crisis). If people feel they are not advancing like they have come to expect, let's blame someone. Many other examples are medical scares, usually exaggerated by the media, such as those that claim that a certain food (or behaviour) causes some illness, like cancer or high cholesterol.
Especially with these health scares, it seems that "susceptibility" and genetic factors play a very big part, in the same way that some people have dangerous allergies to peanuts or mushrooms, while most of us can munch safely on. There are certainly lifelong heavy smokers who show no ill effects. But the correlation with lung cancer is very strong, so maybe we have to assess the risk, and possible play safe.
What does it take before we can accept an allegation of the sort "A causes B"? Well, if when A happens then B never fails to happen, that's probably good enough. Eating Death Cap fungi (Amanita phalloides) pretty certainly causes human death - although there may be exceptions for all I know.
Another test for causation is the counterfactual approach. One can look at what would happen if A does not happen. If all other factors are the same, then if B does not happen that may help confirm a theory of causation. But a) if the person has already died, one cannot go back and do the test; and b) all things are not usually equal.
Something else that may lead us towards accept a claim of causation is if we can understand the mechanism of how B (the result) happens when A (the alleged cause) happens. We have no trouble accepting that dialling a phone number causes a ringing on the apparatus at the number being dialled - but this is man-made equipment. There are probably many medical situations where the professionals do understand the mechanism that makes something cause an illness. But the chain of consequences between a government decision and economic results is much less clear.
A common everyday situation is that someone asks "why did X happen?" X could be that there was a bad bush fire, or their team lost a big game, the value of their investments plunged, or a relative was diagnosed with cancer. It is a natural human response to ask "why". However those to whom the "why" question is put may be uncertain as to how to answer. Does the asker want to know the chain of correlations and causes that led to the current situation ("how did it happen?"), or are they really asking "what is it all for?' or "what's the purpose?"
The Greek philosopher Aristotle, who was revived in Europe in the Middle Ages, proposed Four Causes (or as some people have called them, "4 be-causes"), namely the Material, Formal, Efficient and Final Causes. My rough understanding of these is as follows.
| Material | - because it's made of certain substances |
| Formal | - because it's structured in this way |
| Efficient | - because certain external things affect it |
| Final | - because that's how things like this behave (maybe extended to "because this is the way of the world", or "that's life"). |
The first three are covered by what I earlier called the mechanism. The fourth is sometimes referred to as the Teleology, and implies that everything has a purpose. Some religious people would align this with the concept of "God's plan", although that was not Aristotle's idea. Although science may gradually expand our understanding of the mechanisms, if a child asks "why did Grandma die?" when she may have died peacefully and primarily of natural causes, what other answer can we give?
The "Cause versus Correlation" problem may explain all the current argument between climate change proponents and sceptics. Sure, we are seeing some warming and strange weather swings, and certainly our carbon emissions have risen too. But can we be sure that one causes the other? Maybe it is one factor out of many, and we don't know how much warming is due to carbon emissions. Maybe we ought to play on the safe side. But the impression is that the hidden agendas of both proponents and sceptics looms much larger than any science.
The provisional conclusion is that in many cases, all we can safely talk about is Correlation - i.e. that "when A happens, then B tends to happen as well". But that is nowhere near the same as saying that if A happens, then B will certainly happen.
For more of my ideas on this, see the section on Cause and Effect in my essay "Religion - a Worldwide Perspective".
The views here are nothing new - they go back at least to Hume, and even to Aristotle.
Aetiology (Etiology is the US spelling) is the name for the study of causes and effects, but is primarily used in the medical domain, e.g. for causes of diseases and epidemics.
Wikipedia has a page "Correlation does not imply causation". It is a bit more academic that this mini-essay, but gives some good examples.
A simpler explanation is WiseGeek's "What is the Difference Between Cause and Correlation?"
The links below lead to the other components of PLOVER
| Philosophy | Language | Ontology | Value | Evolution | Religion |
Links to other parts of this website
| Back to Evolution A | PLOVER index page | Back to Roger's home page | Back to tagg.org website |
Some of these links may be under construction – or re-construction.
This version updated on 21st June 2012