〈色，戒〉中王佳芝為何臨陣變節，論者多集中對王易性愛的正反辯論，但本文則聚焦失貞一事的重大影響，將色戒辨轉為貞淫論，拼出另一種可能解釋。
第一部份「同夥無心論：集體噤聲」說明同夥對王佳芝的凝視的異化，刻意消音，置她於被噤聲狀態。因此破處成為重大離間。第二部份「同夥有心論：犧牲處女」則檢視父權機制下，同夥是有意犧牲王佳芝，則王在此時已受同夥背叛，被推向 易先生。第三部份「亦貞亦淫：俠女、妓女、妖女」，說明王在社會凝視中的多 重身份與壓力，進行貞/淫之辨，並舉出中外其他人小說為例。王既是女英雄，又是妓女、禍水紅顔。第四部份「被動美女：王佳芝與殷寶潫」則分析張愛玲的 「被動美女論」，為王佳芝的「錯愛」提出解釋，並舉證王佳芝與另一小說中的 殷寶潫的共通之處，兩者可彼此解說。第五部份「美女自戀的悲劇」則探討王佳 芝，其美女自覺過高而導致的假戲真做，與自認遭嫉的疏離。第六部份「李安電 影對失貞的解讀」，則說明李安的個人詮釋，如何分隔破處一事與臨陣變節之間 的因果關聯，進而減損抹煞張愛玲小說本身的虛構藝術。然而失貞的情節設想與 其多層次處理，完全是張愛玲的個人創作。

Instead of joining most scholars’ debates on whether the sex between Wang Jiajih and Mr. Yi is the reason of her betrayal in Eileen Chang’s “Lust, Caution”, this paper offers another possible explanation by focusing on the influence of Wang’s loss of virginity and thus turns “lust/caution” controversy into “chaste/ lubricant” discussion. Part 1 explicates how the comrades’ gazing at Wang’s losing her virginity can be an alienating force and thus an important cause of their disruption. Part 2 examines how “sacrificing the virgin” ideas under patriarchy influence the comrades’ decision, which leads to Wang’s feeling betrayed and pushed to Mr. Yi. Part 3 explains Wang’s multiple identities as a heroine/whore/femme fatale and her chaste/lubricant dilemma, giving related examples from other fictions. Part 4 analyses Eileen Chang ‘s “passive beauty” ideas, providing an explanation of Wang’s “loving the wrong guy” and comparing Wang Jiaji and Yin Bao-yien (heroine of another of Chang’s short stories). Part 5 discusses Wang’s high self-consciousness as a beauty and how it leads to her confusion between playing a role and the real life. Moreover, feeling others’ jealousy toward her also leads to her alienation. Finally Part 6 explicates how Ang Lee’s interpretation separates the cause-and-effect relations of Wang’s losing virginity and her betrayal and thus deduces Eileen Chang’s art of fiction. However, Chang’s invention of the plot of “losing virginity” and her sophisticated handling of this theme show what the movie version seriously missed.