17. When Beliefs and Logic Contradict: Issues of Values, Religion and Culture

In real debates, we often don’t think about the validity of the arguments from the strictly logical point of view and we often disagree even before we hear the particular argument. This chapter deals with confirmation bias in reasoning about controversial issues (in this case abortions) and it examines the effect of values (pro-life, pro-choice, neutral), religious and political affiliations on syllogistic reasoning. It shows how our beliefs prevent us from acknowledging the logic to the same type of arguments if they are made by the other side of the dispute. First, evidence of studies showing my-side bias and confirmation bias is presented, together with studies suggesting cultural differences in preference for distinct cognitive style or problem-solving. Then the results from one non-WEIRD (Slovak) sample (N = 321, M age = 20.47 years) are analysed. Participants first indicated their attitudes toward abortions in a short questionnaire (6 items from General Social Survey), then they solved 24 syllogisms, which had conclusions either in line with pro-choice or pro-life attitudes and 12 neutral syllogisms. The results showed that people holding opposing beliefs did display confirmation bias, but this confirmation bias was stronger for one side of the dispute, i.e. “pro-lifers”. Christian participants performed worse in neutral valid syllogisms, but mainly in all types of invalid syllogisms, where they differed by 10% from the non-religious participants. This chapter shows that when beliefs and evidence clash, it is often belief that wins. It is no surprise that people untrained in critical, scientific thinking resort to beliefs as their compass in navigating through the vast ocean of many conflicting information (claiming their origin in research) and many conflicting values (such as rights of children vs. rights of their mothers).