When he began to have much confidence in medicine after mastering Chinese medicine, Ransai was very shocked to read "Kaitai shinsho" (New Book of Anatomy) written by Genpaku SUGITA and Ryotaku MAENO, and decided to learn Western studies.
漢方医学を究め、医学に並々ならぬ自信を持ちはじめたが、杉田玄白、前野良沢の『解体新書』を読み大きな衝撃をうけて蘭学を志す。