Why do we have so many lives?

Because, if you can't keep one friend's secrets in a different box from another's, you'll never have more than superficial friendships. People will learn that you cannot be trusted and won't tell you anything important, particularly if you ever publish things. There are all kinds of things I know that I cannot publish, or repeat from one friend to another; that's the price of intimacy.

Because the ability to change your focus, your attitude, or your mood – to adopt, perhaps, a wholly different personality – by changing contexts is a superpower, not a liability. Put me on the karaoke stage and I'm a big ham; put me in a suit and I'm a professional; put me in a library with a math book and I'm a mathematician; put me in the kitchen with a chef's knife and I can make dinner. I don't try to solve complex math problems on the karaoke stage, and if I can't stop thinking about cooking in the library I'm not going to enjoy doing math problems. My programmer self turns out to be annoyingly nonverbal when he's focusing, so it's a good thing he's not always around or my poor friends and relatives would never hear from me.

And because the idea that one has a unitary, consistent, conscious personality is ultimately an illusion anyway. I've read enough psychology and philosophy to know this, but I've also met enough Alzheimer's patients to understand this.

There are other reasons, but this is a start.

I pride myself on being able to move between many different worlds, being able to communicate and befriend different kinds of people. I don't speak the same way to my peers and to 50-year olds. There's nothing wrong with that. It's challenging, but it's good for the mind. Moving successfully in different cultural circles gives you better perspective on the cultural forces which unconsciously shape you and your peers.

"Just be yourself" is one of those overly facile pieces of common advice that is more harmful than helpful.

(I feel like the author doesn't say enough to distinguish the personality differences between the example lives and the new "single" life.)

I'm all for reducing complexity in one's life but not at the cost of surrounding myself with people that challenge my own understanding and beliefs. They're not there to convince me to change my mind, instead they help me solidify my position better. Having different parts of one's personality is important to not become a narrow-minded or uninformed individual. Your own personality facets shouldn't be so divergent that you change so much in different social situations and never move beyond superficial communication.

If I only ever focused on one facet of my personality I wouldn't learn anything. That seems counter to the approach an entrepreneur/founder would need to be successful.

Do we really have many lives or do our lives have many facets?

I think there are some people who actually have multiple lives, but most of us just have many sides because we have to deal with people in different ways, but it's nowhere close to being whole other person with a different life.

I saw the title and I thought: oh, an article written by a younger person. And boom, sure enough, there it was.

I do not mean that as a ageist comment at all. It's just one of the things I've noticed about younger people is that they feel there are all these different lives. And somehow they must choose between them. To me, part of the reason why is that they confuse who the actor and who the responder is.

To assume there are all these different lives, you must assume that there are all of these different social groups that "tell" you what to do and how to act. Then you respond doing as you are told. It's not that this is a lie, it is just woefully incomplete. A better way of looking at things is that you are the person communicating. As a good communicator, it is your job to communicate things in ways various groups can consume. For my existentialist friends, being deep does not preclude being authentic.

So no, I don't tell the same off-color jokes in a religious group as I would when going out with friends to a bar, but that's not because I am a different person, am trying to live a different life, or any of that. That's because I have learned that to effectively communicate with some people, off-color jokes shut them down. All communication ceases. This is bad for me and for them. So I choose to adapt my communication style. They can still know that I like an off-color joke -- I'm not hiding who I am or trying to change myself -- it's just that I'm smart enough not to share those things with them.

Something I've been cogitating on for a while: I think that younger people have kind of a hole in their life where they don't really know who they are. Probably a natural part of growing up. Because there's this uncertainty of their own personality, it's rather easy to begin to feel as if perhaps you have more than one! (Perhaps people of all ages feel this way. For some reason it is much more noticeable in younger folks. I know I felt this way when I was younger.)

Having said that, I'd also add that there's a difference between personal and public information. I am a firm believer in honesty and openness. But that doesn't mean that I have any responsibility to dump my life story on random strangers. It just means that for those things I choose to share publicly, I choose to be as honest as possible about them. Given the context.

In fact, for sake of argument I'll take the opposite opinion (I love being a contrarian!) I'd argue that most people are really, really bad at being able to adapt their communication skills to a wide range of audiences. Instead, they seem to feel that nuance and depth are somehow deceptive. I blame this on many things, but technology definitely plays a role. When everything you do or say is public, it has a tendency to turn you into a one-dimensional person. That's a shame. It lowers the level of civil discourse for society as a whole.

"Life is much more successfully looked at from a single window, after all." -- The Great Gatsby