I came across a math problem, said to be a Tokyo University entrance exam question: prove that π > 3.05. To solve this problem, you need to know how π is defined: the ratio of circumference to diameter. You can start with a square inscribed in a circle, then a hexagon, octagon, 12-sided polygon. Break down the complex problem into small pieces, small enough, and solve them one by one. ...
Sometimes you worry about a problem, but there’s no answer right now. A few days later, the solution comes to you unexpectedly—it walks up to you on its own. The situation develops naturally. If you’re ready, the problem gets solved. The key: be ready when chance comes.
Last night I was reading a book and wrote notes directly on the pages. I want to teach my daughter: reading is a dialogue with the author. When you have something to say, write it down. Keep doing it, and things will change. The act of annotating while reading transforms passive consumption into active engagement. The margin becomes a space for conversation.
I’ve been learning tennis with a private coach for about a month. The coach feeds balls but doesn’t explain technique deeply. So I started experimenting on my own. I tried changing my grip—moving from semi-western toward western direction. When you’re stuck, you have to make changes yourself. Change starts from reflection. The key insight: be flexible. Don’t just wait for someone to tell you what to do. Observe, experiment, adjust. ...
I read the book “A Guide for the Perplexed,” and I have an idea. In chapter 3, it describes how man becomes man—why humans are different from plants and animals. Humans can make predictions based on the current situation and adjust their actions accordingly. This reminds me of the difference between chat AI and agent AI. High-level AI should act like a normal human, with the ability to predict and adjust actions accordingly. ...
Maybe I’m getting old, and my memory seems to be getting weaker. I have to accept the reality. I’ll rely more on paper and pens - write it down, if I forget, check the notes. That’s acceptable. My understanding and comprehensive ability is still there, getting stronger. I think after a whole day’s tough work on Friday evening, you deserve a nice dinner and games at home. Spend time with your loved ones, forget work, enjoy doing nothing! Wow, that’s good! ...
Phone is the vessel of overly concentrated pleasure. All the popular apps like Xiaohongshu, Instagram, and TikTok are the sources of that pleasure. NOT games. These apps are all attention black holes—you scroll your iPhone, time is killed, and you’re also being killed. The designers use the weakness of humanity to profit. I have to train myself and my family to get away from those addictions purposely. Long-lasting fulfillment comes from the writing process—you post it on social media and receive lots of comments that are useful to them. ...
I have a habit of writing down my thoughts—kind of a diary, from time to time. So I often review what I’ve written, and that’s enough. It does the same thing. The important part is writing itself, whether you write it right away or later. Writing is thinking. You’re not thinking if you don’t write. And I write. I am what I am. That’s enough. As a vessel, I came into the world, absorb the world into myself—physically and mentally—shape my body and mind. ...
I recently became a tennis fan and a beginner on the court. At first, I tried to hit every ball and force it to the opposite court. I tried hard, hit hard—and played badly. My technique was poor, I couldn’t last long, and I wasn’t learning. I didn’t pause to reflect; I just kept swinging. The result was exhaustion and unforced errors: balls flying long or dying in the net. ...
I was rereading the “Coffeehouse Conversation” in Hofstadter and Dennett’s The Mind’s I when an idea struck me. The conversation probes the limits of the Turing test, and by extension, the nature of machine intelligence. And you can feel that same limit with today’s large language models. Even they are too much more powerful, but they still operate in a closed digital loop. They are too perfect to be creativity. ...