According to canon lawyer Ed Peters: “a woman who has not freely engaged in penile-vaginal sexual intercourse is a ‘virgin’ while one who has engaged in that act is not.” This ridiculously narrow definition permits a woman to commit all manner of unnatural sexual acts, while still claiming to be a virgin.
According to St. Thomas: “the purpose of perpetually abstaining from this pleasure is the formal and completive element in virginity.” The pleasure in question is sexual climax. So if a person obtains sexual pleasure, willingly, by any means, whether masturbation, natural intercourse, or any unnatural sexual acts, that person loses their virginity.
What if a young woman decides to have sex with a young man, both being of legal age, and the woman does not reach climax during her first sexual encounter? Is she still a virgin? Clearly, she is not. She willingly chose to have sexual intercourse, thereby losing her virginity. So the definition of St. Thomas needs to be broadened somewhat. Not only a person who willingly obtains sexual pleasure loses their virginity, but also anyone who willingly chooses a per se sexual act of any kind, with or without climax. For the definition of a sexual act does not, of necessity, include climax. For example, amplexus reservatus is a gravely immoral sexual act which lacks climax for both the man and the woman by definition. In another example, if a wife has natural sex with her neighbor, but she does not reach climax, she has still committed adultery. There is no loophole which permits someone to call themselves a virgin, as long as they have not reached climax, or have not had penile-vaginal sex.
In my definition, a virgin is a human person who has never willingly engaged in any sexual act, with or without climax, including the sexual acts of masturbation, natural intercourse, and any type of unnatural sexual act. Moreover, if a person deliberately uses pornography for the purpose of sexual pleasure, virginity is lost.
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