Demanding the morally demanding: Experimental evidence on the effects of moral arguments and moral demandingness on charitable giving

What are the effects of confronting people with moral arguments and morally demanding statements to perform certain actions, such as donating to charity? To investigate this question, we conduct an online randomized experiment via Prolific (n=2500) where participants can donate to charity. Using a between-subject design, we provide some participants with a moral argument as to why they should donate. We then add a single sentence on top of the moral argument that expresses and varies moral demandingness at different levels. To reduce experimenter demand worries, in a follow-up experiment (n=1200) we provide the same stimulus via an external party's website—the non-profit Giving What We Can. In both experiments, we find that moral arguments significantly increase both the frequency and amount of donations compared to the control. However, we fail to find evidence that increasing the level of moral demandingness affects donation behavior in either experiment. Exploratory equivalence tests provide evidence in favor of such a null effect. Our findings suggest that charities should employ moral arguments to increase giving, though our findings give no specific recommendation as to the moral demandingness employed as there is no additive effect of morally demanding arguments.