noun
leading theory; widely-accepted theory
Refers to a theory or explanation that is considered the most plausible or widely supported among experts or the public.
この事件については、事故だという有力説がある。
Regarding this incident, there is a leading theory that it was an accident.
専門家の間では、それが最も有力説とされている。
Among experts, that is considered the most widely-accepted theory.
通説 is a commonly accepted view, often less strong than 有力説 which implies it is the most plausible among competing theories.
Compound of 有力 (influential, strong) and 説 (theory, opinion).