Quickly, Han Sen noticed he was able to read the text contained within the diary. It was written in the ancient language of humans—a text often used by the crystallizers. There were, however, a variety of symbols not even he could understand. All-in-all, he didn't understand everything together.
There were some formulas jotted down. Han Sen wasn't very good at science. He had learned a bit in school, but he had forgotten most of that by now.
But Han Sen was still able to tell he had never seen these formulas before. They were extremely complicated. Judging from the content of the book, the man had been trying to calculate something.
Han Sen flicked through the pages of the book, and the man showed no reaction. As long as Han Sen made no noise, the man didn't mind his presence there. That's how it seemed, leastways.