In 2009, essayist William Deresiewicz delivered a lecture at West Point on the importance of solitude to leadership. He says that true leadership means being able to think for yourself and act on your convictions, and that knowing what you believe requires solitude, of which there are four types: the concentration of focused work, sustained reading, introspection (talking to yourself), and friendship (talking to another person you trust). I’ve excerpted my favorite grafs below, although it’s worth reading in its entirety.

On thinking:

Multitasking, in short, is not only not thinking, it impairs your ability to think. Thinking means concentrating on one thing long enough to develop an idea about it. Not learning other people’s ideas, or memorizing a body of information, however much those may sometimes be useful. Developing your own ideas. In short, thinking for yourself. You simply cannot do that in bursts of 20 seconds at a time, constantly interrupted by Facebook messages or Twitter tweets, or fiddling with your iPod, or watching something on YouTube. I find for myself that my first thought is never my best thought.

My first thought is always someone else’s; it’s always what I’ve already heard about the subject, always the conventional wisdom. It’s only by concentrating, sticking to the question, being patient, letting all the parts of my mind come into play, that I arrive at an original idea. By giving my brain a chance to make associations, draw connections, take me by surprise. And often even that idea doesn’t turn out to be very good. I need time to think about it, too, to make mistakes and recognize them, to make false starts and correct them, to outlast my impulses, to defeat my desire to declare the job done and move on to the next thing.

On the value of books:

So why is reading books any better than reading tweets or wall posts? Well, sometimes it isn’t. Sometimes, you need to put down your book, if only to think about what you’re reading, what you think about what you’re reading. But a book has two advantages over a tweet. First, the person who wrote it thought about it a lot more carefully. The book is the result of his solitude, his attempt to think for himself.

Second, most books are old. This is not a disadvantage: this is precisely what makes them valuable. They stand against the conventional wisdom of today simply because they’re not from today. Even if they merely reflect the conventional wisdom of their own day, they say something different from what you hear all the time. But the great books, the ones you find on a syllabus, the ones people have continued to read, don’t reflect the conventional wisdom of their day. They say things that have the permanent power to disrupt our habits of thought. They were revolutionary in their own time, and they are still revolutionary today.

Again, it’s worth reading in its entirety.