But I also noticed times when I mistook benevolence for selfishness, times when my motive was all about avoiding a difficult, but necessary, conversation. I struggled greatly to be honest with my husband about how I had developed intense feelings for another man. Once I finally spilled the truth, it opened up a conversation about our very different expectations of marriage — mine turned out to be very high, even though I hadn’t fully acknowledged it. We navigated our way around unhelpful emotions like blame and found each other again, ultimately coming out stronger. But I never would have understood who I was inside my marriage without the conversations my honesty forced.

3. We have to be more honest with children than ever before.

Research from the Massachusetts Institute of Technology showed that when adults don’t give children the whole truth, children work to fill in the gaps — and are then less likely to trust the adult. Victoria Talwar, a psychology professor at McGill University, has found that as children grow, they develop increasing confusion around truth and lies, especially when parents tell them lying is wrong, but then proceed to lie in front of them.

There’s also this: Telling kids the difficult or awkward truth is a great chance to impart values. I learned this from the sex educator Amy Lang, author of “Birds + Bees + Your Kids.” So when my very curious middle-schooler asked me if a certain slang term meant oral sex, instead of changing the topic or squirming out of answering, I was able to say, “Yes, and … oral sex is a way that people like to be sexual without worrying about getting pregnant. It’s part of a healthy sex life. But it’s definitely not for kids. It’s for later.”

With so much information at our kids’ disposal — my kids are now 11 and 9 and fully understand how to use the internet — it’s absolutely not the time to abdicate on talking about the uncomfortable truths, whether it’s sex and consent, racism, gun violence or suicide. Changing the topic is no longer an option for me as a parent in 2020.

4. We lie at work to protect our identity.

Keith Leavitt, an ethics researcher and associate professor at Oregon State University, has found that workplace lies are often related to protecting our identity, whether we define ourselves through our achievements, through the roles in which we serve others, or through belonging to a group. “We tend to tell three kinds of lies at work: lies that protect my own accomplishment, lies that protect someone I’m close to, and lies that protect my company,” Dr. Leavitt says.

When people feel pigeonholed by the way they define themselves — to the point that it’s the only way they can see themselves — they often use deception to double down on that identity. Elizabeth Holmes, the disgraced founder of Theranos, is an extreme example; a less serious example might be the professor who quickly changes the station to NPR before a colleague gets into the car. The challenge, Dr. Leavitt says, is to be able to pivot to another identity when you feel threatened. The star saleswoman who failed to win the contract, for example, could remember that she is also a mentor.

5. The biggest lies we tell are to ourselves.

Zoe Chance, a professor in Yale University’s school of management, has shown that even when people do well on a test because they were allowed to cheat, they still see themselves as responsible for their success. People in her experiment who were allowed to cheat on a test in which an answer key was “accidentally” made visible kept predicting they would do well on future tests that didn’t contain an answer key. It took them doing poorly on two more tests before they finally realized they probably weren’t going to do so great without the answer key they had on the first test.