A false belief unexplained by reality, shared by a number of people is:
A. i.e. SuperstitionNormal thinking is characterized by smooth & continuous flow or fluency (continuity), reasonable speed, clear goal directed logical organization (clarity & organization), with a logic, sequence, intent and control. Whereas, constant/firm belief held on inadequate grounds is delusion.
Superstition
Illusion
Delusion
Obsession