(=> (Competitor ?Competitor) (Or (Exists (?Vendor2) (Competitor-Of ?Competitor ?Vendor2)) (Exists (?Vendor1) (Competitor-Of ?Vendor1 ?Competitor))))
(<=> (Competitor ?Competitor) (And (Vendor ?Competitor) (Qua-Entity ?Competitor) (Or (Exists (?Vendor2) (Competitor-Of ?Competitor ?Vendor2)) (Exists (?Vendor1) (Competitor-Of ?Vendor1 ?Competitor)))))