One of our fundamental needs is to understand the causes of events, why things happen. Such causal knowledge allows us to better predict events, and this gives us a sense of stability.
It stands to reason that most messages in social advocacy and political influence will be much more effective if they include causal arguments which explain why something happens and inform about the underlying mechanisms.
Changing Erroneous Beliefs with Causal Arguments
Let’s say you want to change people’s belief that HIV is transmittable by contact. Many people, observing that flu and other viruses spread through casual contact, thought (and still think) that HIV/AIDS virus spreads the same way. You could tell people that there was never a single proven case where the AIDS virus was transmitted by casual contact. Moreover, you could mention various statistics or expert reports supporting your point. Or you could try explaining the underlying mechanisms of AIDS and why the virus couldn’t be transmitted through casual contact.
A 1996 study by Morgan Slusher and Craig Anderson tried to change such erroneous beliefs about AIDS. They tried to persuade some of their subjects with statistics, such as this passage:
A study of more than 100 people in families where there was a person with AIDS without the knowledge of the family and in which normal family interactions such as hugging, kissing, eating together, sleeping together, etc., took place revealed not a single case of AIDS transmission.
With others, the researchers tried causal arguments, such as this one:
The AIDS virus is not concentrated in saliva . . . The Virus has to be present in high concentration to infect another person, and even then, it must get into that person’s bloodstream . . . This virus is very fragile . . .[S]tomach juices would kill the virus . . .[W]orkout partners did not get the virus because it was not present in sweat.
As expected, causal arguments proved much more effective. One reason is that causal arguments replace readily available explanations. One difficulty in changing such erroneous beliefs is that people already have a readily available explanation, albeit an erroneous one. What’s more, the most “intuitive” explanations are also the most easily available explanations, and such explanations normally create beliefs which persevere even when rational evidence shows them to be illogical. So statistics or other non-causal arguments normally will not replace existing and easily available explanation, but causal arguments make alternative explanations available.
Causal Arguments and the Power of Storytelling
Storytelling is a potent tool of persuasion because stories are based on causal structure. Normally, stories make causal relations very clear, and we can easily understand why particular events happened, what motives led people to do what they did. Of course, causal structure is not the only reason why we are swayed by stories. Stories are also very engaging, and while being engaged, we usually lack cognitive strength to counter-argue or doubt explanations provided in the story. 
- Whenever you want to convince people that something is true, try to explain why it is so, what are the underlying mechanisms of the problem.
- Preferably, use stories in which causal arguments are embedded.
 Morgan P. Slusher and Craig A. Anderson, Using Causal Persuasive Arguments to Change Beliefs and Teach New Information: The Mediating Role of Explanation Availability and Evaluation Bias in the Acceptance of Knowledge, Journal of Educational Psychology, 88,110-122 (1996).
 Melanie C. Green and Timothy C. Brock, The Role of Transportation in the Persuasiveness of Public Narratives, Journal of Personality and Social Psychology, 79, 701-721 (2000).