When I read Ben Horowitz's last book (The Hard things about Hard things), I had emotionally challenging days. I was running my own startup, and the figures were getting despairing. So, I was attuned to the book line by line. The book has come to one of my life books, but I never want to reread it.

Now, in my heyday as an engineer, I can read his new book "What You Do is Who You Are (Ben Horowitz / Harper Business)" in a tranquil mind. The story of Louverture's Haitian Revolution was very intriguing to me as I hadn't had any idea of it. Shaka Senghor's anecdote was like 100m/h straight. I could understand how the weird startup rules (e.g., "Build fast and break things.") actually work. This book explains how we can build company culture with object lessons.

However, I believe the central idea of this book is the title itself.

It's what you do. What you do is who you are.

I have met and known a lot of people in my life. Many had good philosophy, theory, and words. But I think we can understand them when we see what they're doing: How they behave when seizing the initiative, how he/she treats their waiter at restaurants, how they behave when their value and benefit conflicts, and so on. The culture is not made by statements. It is created by the behavior of members and what makes them behave so. My most significant loot of this book is that I've learned a new English idiom: "Walk the talk."