References the general theory that when a Wikipedia user is on any given Wikipedia article the user is never more than 6 clicks away from something directly related to sex, either through related articles or text-embedded links.
*Note: 6 clicks is a conservative number, in everyday practice the average required number of clicks is lower.
Wikipedia Rule example link paths:
Starting article: William Howard Taft. 1>Serial Killers. 2> Sex.
Starting article: Brooklyn Bridge. 1>Pedestrians. 2>Health. 3> Reproductive Health. 4>Pregnancy. 5>Vagina.
Starting Article: Manganese. 1>Pigment. 2>Cosmetics. 3>Human Body. 4>Male Reproductive System.