This (a site built by putting to use the analytical data from reading every preface and afterword) is made by a person whose hobby is building small systems.
How to Build a Small System
To learn systematically means to receive an advanced education and acquire ordered knowledge. You can get it by studying at school, or by reading a well-structured textbook. Human intelligence has already laid out the path for you. This way of learning is efficient. But it suits some people and not others. I am one of the ones it does not suit.
You read a lot of something, wherever your interest takes you. With some exceptions, no matter how much you read this way, you do not end up with systematic knowledge. When you read miscellaneous things and your stock of knowledge grows, what you have is a head full of miscellaneous events. There is no frame to connect the knowledge at a higher level. This is the way I like. So I had no systematic knowledge. It is not easy to become one of the exceptions.
That is the story up to now. Then digital archives appeared, and the situation changed.
Digital Archives Changed How We Learn
In the early days of digital archives, the search function was weak. It was an age when all you could do was read whatever came up. In that period I wrote a book about Meiji entertainment fiction. I never counted, so I do not know the exact number, but I read an absurd amount of Meiji entertainment fiction. I still could not build a system.
Before long, search in the digital archives got a little better. When I wrote a book about simple living (kan'i seikatsu), I searched for 『simple living』 and clicked and read every one of the roughly 2,000 links in the results. That one came close to a system, but it was still a little short.
After simple living, I began looking into working one's way through school (kugaku) and penniless travel (musen ryokō) in Japan. Full-text search became possible in the digital archives, and magazines became readable too. I checked the entire list of results — about 12,000 for kugaku, about 7,000 for penniless travel — and read the important ones. With that, my knowledge of kugaku and penniless travel became a system.
Thanks to the advanced functions of digital archives, it became easy for a person to build a small system. What is different from before?
What I have read the most of is Meiji entertainment fiction. "Read an absurd amount" does not turn into a system. For kugaku and penniless travel I checked a combined list of 19,000 items, but read only the important ones. What built the system was not "how much I read."
In the age of poor search, all you could do was read whatever came up. The branches ran from Meiji entertainment fiction to simple living, to kugaku, to penniless travel, and miscellaneous things piled up in my head. Even so, the whole never came into view. What you cannot see, you cannot connect. Points stay points.
With full-text search, the range widens to 12,000 for kugaku and 7,000 for penniless travel. By checking through them, the field acquires a boundary. You stand at the center, and you can see what is common, what is rare, and what is missing. That is how a small system gets completed.
Inside a small system, miscellaneous knowledge comes alive. Parts of Meiji entertainment fiction and simple living are built into the small system of kugaku and penniless travel.
Meiji entertainment fiction and simple living could be made into small systems at any time. But so far I have not done it. Because there is no need. To build this, because I needed it, I built a different system.
The System I Built, and the Systems You Could Build
To build a small system, I first collected 365 days' worth of human behavior. It was training in collecting as flatly as possible, once I knew objectively what kinds of human behavior I like. This by itself does not become a system. Because it is points.
After that, I read every preface and afterword in the books published in the year following the end of the war. This did become a small system. The 365 days' worth of human behavior was built into it. And then this site came out of it.
What I do, anyone can do if they have free time. Even without free time, you can do it if you put in the hours. Narrow the range, and you can do it a little more easily.
https://dl.ndl.go.jp