Since entering the school, Kanetane knew that his teacher Atsutane studied mysterious things and the underworld to restore the ancient belief which had been lost or sealed up, besides Kanetane understood that Atsutane tried to prove the existence of mysterious things by Kodo; about 1820, by Yoshinari YAMAZAKI, a learned amateur living in Shitayachoja-machi and an acquaintance of Kanetane's friend Hirokata YASHIRO, Kanetane was introduced to Sendo Torakichi, who could come and go freely to the underworld, then Kanetane became convinced of the existence of the underworld, and began to put in serious efforts to collect information of mysterious stories and materials of such things.
入門当初から鐡胤は薄々感じ取っていたが、父篤胤の幽冥・死後の世界の研究は、失われて埋没され、そして封印された古代信仰の雛形を元の姿に復元させる為の学問であり、其の為に古道の道に足を踏み入れて幽冥の存在を立証しようと試みていた事も知悉していたが、文政3年頃に知友屋代弘賢を通じ下谷長者町の博学の好事家山崎美成を介在して、後に父のもとを訪ねてきた異境を往来すると言う仙童寅吉の姿形を目の当たりに見て、父篤胤が唱える幽冥界の実在をしかと確認し、以後は自らも寸暇を惜しみ、不可解な奇譚の情報やその他の幽冥関連の資料類の蒐集に没頭する事になる。