Quick — what’s a secret you’re holding on to right now?

Perhaps the most revealing thing about that question is the kind of answer that leapt to your mind. Did you think of a small, relatively inconsequential thing like, “I didn’t shower this morning“? Did you think of something great that made you light up, like, “I’m throwing my best friend a surprise party tonight”? Did you think of something from the past that you still feel ashamed about — an affair, a crime?

Author, researcher and Columbia University professor Michael Slepian is a professional expert on secrets. He’s devoted much of his career to exploring why we keep them, who we tell them to, and the effects they have on our minds and our relationships. And in his revealing and entertaining “The Secret Life of Secrets: How Our Inner Worlds Shape Our Well-Being, Relationships, and Who We Are,” Slepian pulls back the curtain on all the ways we rely on our secrets — and, at times, the sharing of them — revealing the hidden lives of our lives. 

Drawing on research with tens of thousands of subjects around the world, Slepian’s been able to create a kind of taxonomy of secrets, and even estimate how many secrets — both big and small — you’re keeping right now. Yet as he describes in the book, what he hadn’t imagined when he began his work was there was a secret lingering within his own family too. Salon spoke to Slepian recently via Zoom about our fascination with secrets, the ones that weigh on us, the ones that thrill us — and the ones we should probably give away. 

This conversation has been edited and condensed for clarity.

You start out the book with learning a family secret of your own, and how your work influenced your parents’ choice to come forward with it. What has changed in your understanding of secrets in the nine years since? It really did upend your life in certain ways.

Certainly from a research perspective, we’ve learned so much since then. But as I’m learning this big family secret and at the same time shifting toward understanding secrecy itself, we’ve learned so much. We’ve learned the whole angle of [how] it’s not the hiding, it’s the having to live with it. That was something that came later. It’s really changed how I think about secrecy. In my own life, I try to not have a secret that I’m the only one who knows. I try to confide in people whenever I can. It’s certainly changed how I deal with secrets in my own life, and that we’ve learned so much since then about how secrets affect people.

You talk about cultural secrecy, but we also have different generational ideas about secrecy. We live in such a confessional culture now. What is different? What is changing? What’s good about that?

I think you’re right that in olden days, secrecy was a way to deal with problems. “Just don’t talk about it” was a solution to something uncomfortable or something that other people would find scandalizing. Family secrets are a really good example of this. Today, people understand that’s not the way to deal with problems, more so than in prior generations. Young people today are much more encouraged to speak their mind, to share their feelings and to find words to describe their feelings.

This is just my observation from afar. I don’t have children myself, but it certainly seems like people are more in line with talking about these things. I feel like in the ’90s, there was this idea of the sensitive man who talks about his feelings that sounds weirdly dated today. It’s because of what you’re talking about here, that we understand that the way to get help from other people or the way to solve a problem is talking about it.

You make distinctions in the book about the types of secrets we carry and the ways in which they affect us differently. “Secret” is such an all-encompassing word. What are the secrets that are the worst for us to carry around?

The ones that hurt us the most are the ones that are constantly on our minds, the ones we feel at a loss for what to do, or the ones we feel ashamed with or feel inauthentic keeping. When you keep something entirely to yourself, it’s very hard to find a healthy way to think about it, especially if it’s something that’s bothering you or upsetting you. So the secrets that harm us the most are the ones that we feel upset about or bother us and we are the only ones who know them. And it’s something that our mind turns to time and time again.

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Certainly, if there’s a secret that you’re struggling with, keeping it entirely to yourself is not typically going to help you move forward. That requires talking about it with someone. It doesn’t have to be the person you’re keeping the secret from, but just someone you can trust, someone who should be able to understand it.

When we talk about who you should confide in, we say someone who will keep your secret safe. It turns out that the average conversation about a secret is helpful. Someone has to respond very negatively for you to feel like you did the wrong thing for confiding to have backfired. Even just a lukewarm response, people find typically helpful. Other people have perspectives that they can share with you that are hard to find on your own. Other people can offer you emotional support or validate your experience or just listen. That’s something you can’t get on your own. There’s so much that other people can offer you when it comes to a secret like that.

There are the secrets that we keep because of our own sense of shame or stigma. There are also the secrets that we keep because we want to protect other people, or we don’t want to burden them. That’s very generational. It’s very cultural, these ideas of, “I have to carry it so that someone else doesn’t,” which are different from, “I have to carry it because everything would be taken away from me.” Is there something more positive or affirming about carrying a secret to protect someone else?

When should you keep a secret? If revealing a secret would hurt someone else’s feelings or damage their relationships or somehow lead to something bad, it would seem at least keeping the secret is the right thing to do. Even in that situation, I would advise people to talk about it with a third party, just to be sure. If we’re talking about something big like someone’s cancer diagnosis in “The Farewell,” even when you feel like you’re doing the right thing, you don’t have to make that decision alone. I would still advise people to talk to someone that they trust to make sure that this is the right decision. That other person can really help you think through what is probably a very difficult situation.

You write about happy secrets. There is something special about having information that the rest of the world doesn’t necessarily know yet. What is the benefit of those, and what is it that we love so much about those secrets?

There’s essentially two different kinds of happy secrets or positive secrets. One is the kind with a very clear expiration date. Some of the most momentous occasions start off as a secret — a marriage proposal, some surprise for someone. Gifts often are kept secret until they revealed. What’s really beneficial for the person who keeps that secret is how, even if you have to be careful about what you say, your mind is returning to this thing that you are really excited about. Keeping a happy secret or a positive secret allows us essentially to savor that positive information. It allows us to live with it in our thoughts. It’s something we’re excited about. The more we reflect on or spend time thinking about things that we’re excited about or that we’re happy about, that’s associated with increased life satisfaction. Positive secrets really enable us to do that.

The second thing is, it doesn’t just help us savor that positive experience and think about it. This thing that we’re excited about, we also feel control of. This is the lesson when it comes to our negative secrets. When it comes to positive secrets, we know what we’re doing. We feel like we have complete control over the information. That also is something that feels good. Feeling in control of things in your life is one of the major predictors of life satisfaction. It’s even associated with living longer.

There’s another kind of happy secret. It is one that we don’t plan on revealing. This one really interests me. We’re at the forefront of what we know about this. We’re doing research on it right now. It’s something you feel good about, and you don’t talk about it with other people because you feel like they won’t understand or that they might look down upon it. A lot of hobbies fall into this category.

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Someone who collects stamps might keep it a secret, because they’re like, “I just really enjoy this and I don’t need like other people’s thoughts on the matter.” Those are a little bit different, because there isn’t this plan to reveal them. But still, it’s, “This is something that’s special to me and I feel good about keeping it to myself. I don’t need other people’s thoughts to make me feel worse about it.” It’s interesting because it starts sounding like the other kind of negative secrets, but it’s not. It allows us to keep this thing special to ourselves and it makes us feel good.

The types of secrets that we feel the worst about aren’t surprising — you’ve hurt someone, you’ve been unfaithful. But I was surprised to see how often pregnancy and abortion came up, because that is a secret that women uniquely carry. Do women experience secrecy differently? And is there a gender that is more likely to share secrets?

That’s the one big gender difference. We see women are more likely to confide their secret in a third party — not reveal the secret to the person they’re keeping it from, but more likely to confide in others. Why? It’s research that we need to conduct still. But I think it gets wrapped up in these gender roles and stereotypes of how we expect men and women to act and this idea of being emotional and making yourself vulnerable. That’s what it means to confide a secret in someone. You’re making yourself vulnerable and you’re asking for help in a lot of cases. That lines up with what we think about gender stereotypes. Why don’t men feel comfortable opening up? I think it comes down to these gender roles.

As far as the different kinds of secrets that people keep, the only gender differences we see are about having that experience in the first place. For example, abortion, that’s going to be a secret more women keep of course. So when we see gender differences in the kinds of secrets people keep, it’s driven by gender differences in experiences people have in the first place.

Let’s talk about the number of secrets we keep. The book theorizes we are carrying up to around a ballpark of 13 at any given time. What is that doing to us? Is there an optimal number of secrets we should be keeping?

One of the first major stepping stones of understanding how our secrets affect us was just simply creating a list of common secrets people keep. We asked a couple of thousand people, “What’s a secret you’re currently keeping?” We looked at those thousands of responses and looked at the common themes that emerged. It turned out that with 38 categories of secrets, we could really comprehensively cover what people typically keep secret. When we show this list to people, we see that very typically people have at least one secret from that list. On average, they have 13 secrets from that list. If we just ask people open ended, “What’s a secret you’re keeping?” 92% of the time it’s one of these 38 categories of secrets.

For something that can feel so personal and so individual and isolating, actually we all keep the same kinds of secrets. We’re all in the same boat, essentially. A lot of what we do in the research is ignore in a sense what the secrets are about, with the goal of being, what are the experiences people have that transcend these common secrets, irrespective of what the secret is about?

It turns out that the secrets that we think about more are the ones that hurt us, not the ones that we hide more. That’s something we know that generalizes across all these different categories of secrets. In starting to think about, “What about the different kinds of secrets?” that’s when we think about these different dimensions. That’s when we start seeing that there are these larger ways that we can sort these 38 categories of secrets.

Some secrets people find more immoral, and those are the ones that cause us shame. Some secrets, people feel are more personal and individual, and those are the ones we feel more isolated with. Some secrets feel more emotional and those are the secrets we feel less certain about that, we feel like we lack insight into.

The number of 13, in some ways it’s an overestimate, but in other ways it’s kind of an underestimate. Let’s say one person has 13 [secrets] from the list, since that’s the average number. In some cases, they’re like checking a box. They’re like, “This is something from a million years ago, but yes, I still keep it a secret.” Those kinds of secrets get included in that number of 13. It’s not 13 currently pressing secrets. It might be only like two or three or the ones that are really impacting you today.

Some secrets just become less relevant to life as time marches on. Those secrets can still hurt you as something that makes that secret relevant again. One interesting thing that I’ve been meaning to study is this idea of when you start a new romantic relationship, all of a sudden these things that didn’t really matter anymore, you’re like, “Well, I guess I have to reveal these things.” They become active again.

So that number 13 includes old secrets that you haven’t thought about in a while. That’s why it’s an overestimate in that sense, because when we think secrets, we think about like secrets that are currently bothering us. It’s also an underestimate in that we don’t allow people to say, “I have four secrets related to finances,” or, “I have three secrets related to sexual behavior.” The number of 13 is the number of categories of secrets that people currently have, not each individual instance of a secret.

When I think of the word “secrets,” I see it in the middle of this Venn diagram with privacy on one side, which most of us would say is a good thing, and then lying, which is a bad thing. What do you think are the distinctions? You can’t really lie without keeping a secret. 

Lying is interesting because lying is a way you can keep a secret. You say something that’s not true because that helps you maintain the secret. But also, you can keep a lie a secret. Like you’ve said something untrue, and it’s really a big thing that you’ve done. You consider this a significant instance of saying something not truthful. If your intention is for that truth to be kept secret, then the lie itself is a secret. People will say that the most common secret that they currently have is that there’s something really big that they’ve lied about. Of course, you can keep a secret without lying.There’s many secrets where all you have to do is just not talk about it and you don’t have to lie to keep the secret. That probably captures a lot of the secrets that we keep.

Where to draw the line between secrecy and privacy comes down to intention. If you intend for other people to not learn this thing, it’s a secret. But there’s this fuzzy boundary with matters that we consider private. It’s not that we are intending to hold it back from other people, but it’s rather just not the kind of thing people talk about. We don’t talk about money with our friends, for some people. We don’t talk about sex at work because it’s not even appropriate. If there’s something that people don’t know about you, but if you got asked a question about it, you would reveal it, that might be closer to privacy. If you got asked about it and you would not reveal it, because you don’t want people to learn that thing, then we’re talking about a secret. But there’s cases where it can be a little mixture of each.

One useful way of thinking about privacy is, this is something I would tell people, but only people I’m really close to. I wouldn’t just tell anyone about this. Those are matters we consider private. But if your friend asks you about something that you don’t want them to know about, that you would not reveal it if asked about it, then we’re at secret.

Relationships are an interesting example because there are some things that the reason that it’s private and not a secret is we just feel it doesn’t make sense to talk about. People will often not talk about prior romantic experiences, prior sexual experiences, with their current partners as a matter of privacy. They just feel like it’s not that they’re holding it back, it’s not relevant to talk about, or it’s not productive to talk about.

Looking at it from the perspective of the person who doesn’t know this thing, if they would consider that thing to be really relevant to know about it, they would consider it a secret. If there’s something that your partner did that you would really want to know about it, then it starts feeling like a secret. Then also if it’s immoral. People will consider something more immoral as a secret rather than a matter of privacy.

I have to ask, when people find out what you do, do they immediately want tell you all their secrets?

It does sometimes will lead people to be like, “What’s a secret I’ve never told someone?” People will sometimes play that game with me. Once in a while, I’ll feel like I want to reciprocate. I’m like, “Well, what’s something I’ve never told this friend of mine?” It does lead to secret sharing, for sure.

More on the science of what makes us tick: 

• Yes, it is possible to die of a broken heart
• ADHD doesn’t just affect young people — and it’s not something that’s just caused by technology
• Is noise bad for us? The authors of “Golden” on why silence is good for your brain