The person who taught Dr. Park Byeong-seon about Jikjisimche was Lee Byeong-do.
Everyone is a pro-Japanese historian.
In Korea, when people were talking about Dangun in vain and saying that Dan was a dandelion tree, bright blah blah blah, it was said that it was Lee Byeong-do who assumed that Dangun was a Tangur tuning fork. Either because of proper research or to disparage the Korean people, there is a term called Tangur in the north, so let’s insert Dangun and disparage the progenitor of the Korean people. I don’t know if the intention was to catch a rat by catching a cow on the back foot, but…
Anyway, after liberation, he completely changed his face and became a leader among Korean historians.