Wanting to learn more about the Dutch East India Company and the Dutch occupation, he began studying Dutch from a Japanese primer and started to make use of the historical materials that had been left behind by a Japanese professor.
由研究交通史入手，自然想瞭解荷蘭東印度公司在東亞的貿易，和荷據時代台灣殖民的情況；他於是開始由日文的荷蘭書入門，也自修古代荷蘭文，更就近利用當年日籍教授留下的檔案資料，研讀整理外，甚至將手稿照片一一打字留存。