According to a new study by Canadian psychologists Nina Mazar and Chen-Bo Zhong, ethically conscious consumers are actually less likely to be kind to others and more likely to cheat and steal. Julian Baggini thinks it through:

The general truth lurking behind these findings is that the feeling of being pure is a moral contaminant. In ethical terms, the best never think that they are the best, and those that believe themselves to be on the side of the angels are often the worst devils.

Why should this be so? One reason is that complacency is as dangerous in ethics as it is in any other area of life where we strive for excellence. If we think we are "good people" we might think less about the possibility that we might actually be doing wrong.

But if that just seems to be a universal truth of human nature, what of the idea that being in moral credit earns us redeemable naughtiness points? I can imagine what the evolutionary psychologists would say: ethics is rooted in reciprocal altruism – you scratch my back, I'll scratch yours. So when you do the right thing, but not to any particular person, we instinctively feel that we have earned some sort of pay back. Since no-one will do that for us, we opt for self-service reciprocation.

(Hat tip: Heather Horn)

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