Question: What modern Japanese martial art was developed by Morihei Ueshiba, often referred to as"the founder" "Kaiso" or "Ōsensei"?
Sentence (from "Morihei Ueshiba"): He is often referred to as "the founder" "Kaiso" (開祖 ) or "Ōsensei" (大先生/翁先生 ) , "Great Teacher".
Relevant evidence: Yes