People frequently think they have to lie to spare someone’s feelings. But your research has found that listeners would often rather hear the truth.

If I see a colleague’s presentation and I don’t think it’s good, for me to give her false praise is a mistake. That’s a white lie that ultimately hurts her, because she could use the truth to benefit herself.

So does that mean we should always tell the truth?

No, there are cases when people appreciate deception. If that same colleague finishes her talk and I tell her, “Can you believe you had spinach in your teeth?” there’s no benefit to that information.

What about the third option — saying nothing?

That’s the biggest mistake, because it doesn’t provide the benefit of information. It also doesn’t provide the emotional benefit of a white lie. A doctor, for example, will say it is much better to tell a patient nothing than to give them false hope. But patients will say, “I would much rather have false hope than for a doctor to give me no information. That’s just making me feel uncertain and imagine the worst.” It’s like the worst of both worlds.

What should you do if you’re not sure whether someone wants to hear the truth?

Just ask. Like, my husband knows that once we’re out, if I ask how I look, I’m not really looking for honesty. I’m looking for reassurance. But if I’m asking at home, when I’m picking out an outfit, then I’m looking for the truth.

How did you become interested in the value of lying versus honesty?

My grandfather wanted to invite all of his friends to my wedding, and I didn’t know any of them. I was really stressed out. My mom told me, “Don’t worry. We won’t invite them.” I found out later that she had photocopied the invitation and sent it to my grandpa’s friends, and none of them came; she knew they wouldn’t. She eventually told me what she’d done, and I was really grateful she hadn’t told me. She understood what I needed.

Does this research make you more aware of how often you’re lied to?

All the time. I give talks, and people tell me, “Great talk.” And I wonder, What does that mean?