Tomorrow I’ll turn 40. Ten years ago, when I was 30, in my (Japanese-only) diary, I wrote, I looked back at what I had learned in my life before and mentioned that my dreams in my thirties were (1) good marriage, (2) success in business, (3) spare financial resources, and (4) possession of my own house. Nothing from those dreams has come true right now, except that I’ve got enough income to manage to support myself.

Indeed, I’ve experienced a wider variety of things in my thirties than I did in my twenties. Years in my thirties were much better, much brighter, and much more exciting than those in my life before. I don’t feel as depressed as I did for a few weeks before I was turning 30. But I think I’ve lost some precious things—time left in my life and a little physical strength. There are 10 years less time left to work, earn, and live. My skin gets duller. There are more wrinkles on my face. I can drink less alcohol. And I get tired more easily.

I think that my forties would be the decade for compromise with and a battle against aging. I will face two types of aging: one that can’t be overcome and the other that I can. I won’t try to fight physical aging too much, which can’t be helped. I won’t stick to what I can’t do, for there is a limit to my ability. Even if I give them up, I’ll have a lot of other things I can do. I won’t grieve over what I’ve lost. Instead, I’ll be thankful for what I still have.

On the other hand, I can fight against mental aging, which means fear of change, adherence to ideas and sense I acquired in the past, and lack of curiosity about new things. This kind of aging can be overcome on my own accord, no matter how old I turn.

The money will be more important to me. Until now, I’ve intentionally spent all the money I’ve earned on my life experiences rather than saving it. Now that I’m in my forties, I have to change my mind, because there will not be so much time left before I can no longer earn any money. I’ll try to save as much money as I can so I can spend my last days comfortably.

The global mind is now crucial for my future life, as well. As a Japanese person, I would like to continue living in Japan until the end of my life. Yet the future is unstable. This country may no longer be safe and comfortable to live in, as shown in the events of the tsunami and radioactive contamination that occurred on March 11, 2011. Some countries around Japan are hostile towards it, so that they may attack our homeland someday. Even if I can’t live in Japan any longer for some reason, I want to be able to live and get a job anywhere else in the world. I’ll build the skills and human connections I need to do it. Of course, I’ll save my assets in several countries of the world so that I can live even if I lose one.

Nobody knows the future, but life is fun for this. I will live the next ten years with fun.