Counting your change as you exit the local supermarket, you discover that the cashier accidentally handed you back a ten dollar bill instead of a five.  You pause, debating whether to go back and correct the error or pocket your modest windfall.

What you do next may depend on how fresh the fruit smelled in the produce section.  If the tomatoes were over-ripe enough to emit an unpleasant odor, that might be all it takes to set your moral compass spinning.

In a series of social science experiments, researchers observed how exposure to disgusting smells or images can influence our attitudes and behavior:  the same self-protective reflex that makes us back away from an assault upon our senses can also make us recoil from offensive behavior.  Needless to say, rotten tomatoes have nothing to do with personal character; but once our feelings of disgust have been activated toward repugnant pictures or noxious odors we are more likely to feel aversion toward objectionable conduct and become increasingly repelled by unethical behavior.

That’s the good news.  What’s really ironic, however, is that the same stimuli that make us less tolerant of improper actions by others make us more likely to engage in those same kinds of actions ourselves.

Read the whole article here.