本文以中古世紀醫學對相思病之觀點分析濟慈在詩中對情愛之呈現，並分析其愛情觀感之轉變。相思病之觀點中，女性被視為引誘男性之魔鬼使臣，在引誘之過程，使用愛情的法術或春藥來魅惑、擄獲其獵物。遭愛俘擄之人常喪失理智、感官及判斷能力，並呈迷戀、荒謬，心緒糾結之狀。
濟慈許多如「拉米亞」 (“Lamia”)和 「無情女妖」 ( “La Belle Dame sans Merci”)之詩作皆描繪出相思病之徵狀。依文獻所示，濟慈創作這些詩作時，也讀著相思病之相關醫學著作，此顯示出濟慈受中古相思病及其性別意識之影響。此外，這些詩作之角色(常為女性)可視為中古意象中〈愛情使臣〉的再現，因為她們引誘男性並誘發各樣相思病徵。
中古相思病論述影響著濟慈之詩作及其生活。濟慈初戀芬妮•布朗（Fanny Brawn）之際即欲逃離愛情之枷鎖，此舉似受相思病影響。然而，無法治癒自身之相思病使濟慈體會到中古世紀對相思病觀點的抑制，相思病及其性別意識下潛伏著的理性思維之束縛，並進而改變其對相思病之信念。
濟慈在「拉米亞」(“Lamia”)中以利西烏斯(Lycius)對阿波羅尼烏斯(Apollonius)的控訴，及「無情女妖」 ( “La Belle Dame sans Merci”)中騎士了無目的的漫遊嘲弄了理性對相思病的詆毀，並在「憂鬱頌」(“Ode On Melancholy”)和「秋頌」(“To Autumn”)中呈現出另類看待相思病之風貌。與其視女性之美為威脅及糾纏，濟慈毋寧認為女性之美提供了一種晦澀不明之愉悅。與其著重在條理分明之男性特性，毋寧說濟慈欣賞、描繪在愛情中男性柔軟、多變、曖昧不明，優柔寡斷之女性特質。濟慈認為女性令人費解之美在一以男性為主的社會，非但不受歡迎且被壓抑，男性尤不被允許展現女性特質及情感。
強調理性的十八世紀未和中古時期二者皆強調男性之沉著、理智。濟慈體會到，與其一昧抵制相思病之女性化病徵，還不如接受可同時展現男女性特色之男性來得健康。情緒波動帶來的衝動是可以被允許的人類情感。洞見相思病後，濟慈治癒了自身對該病之恐懼，不再逃離愛情。在感情的路上，中古世紀性別意識不再牽絆濟慈。

This thesis adopts the medieval medical discourse on love melancholy to analyze the representation of erotic love in Keats’s poetry and to the changes in his ideas concerning love. In medieval discourse on love melancholy, women are seen as demonic agents to seduce men. In the process of their seductions, these temptresses also use amatory magic and love philters to bewilder and to enthrall their “games.” People who fall in love usually lose their minds, their senses, and their judgments. They appear obsessed and insane, which leads to weakness, absurdity, and mental obscurity.
Many of Keats’s poems depict lovesickness, such as “Lamia” and “La Belle Dame sans Merci.” There are evidences showing that when he was composing these poems, he was also reading medieval treaties on love melancholy, which suggests that he might to a great extent be influenced by medieval concepts on lovesickness and sexuality. The characters in these poems, furthermore, can be seen as representations of the medieval images of the “agents of love,’ who, usually female, seduce men and cause all kinds of symptoms of “love.”
Keats was influenced by medieval discourse on lovesickness not only in his poetry but also in his personal life. When he first fell in love with Fanny Brawne, seemed to act under the influence of the so-called “love-sickness,” and he strived to escape from love. Nevertheless, his failure to cure himself of this “disease” enabled him to perceive the restraining viewpoint of this medieval discourse in regard to being love sick. Realizing this restrictive rational ideology lurking behind the medieval ideas of love melancholy and sexuality, Keats changed his belief in lovesickness.
With Lycius’s accusation of Apollonius and the knight’s aimless loitering, he satirizes in “Lamia” and “La Belle Dame sans Merci” the derogation of reason on lovesickness, while in “the Ode on Melancholy” and “To Autumn,” Keats represents melancholy in a way that differs from the discourse he has inherited. Instead of showing feminine beauty as threatening and haunting, he delineates it as giving a perplexing delight. Rather than sober male characters, he prefers and describes indecisive male characters in love who demonstrates qualities such as softness, capriciousness and uncertainty—qualities usually associated with females. Keats came to realize that the female perplexing beauty is suppressed and disliked in a society dominated by men, and males were not allowed to express feminine traits and emotions. The emphasis on rationality in late-eighteenth century somewhat resembled the medieval times in that both emphasize male calmness and intelligence. However, experience enabled Keats to realize that, rather than singularly repel the feminizing symptoms aroused by love melancholy, it is healthier to accept both the female and male features demonstrated within a man. Emotional perturbation and temporary irrational passions are human emotions that should be permitted. Instead of running away from love, Keats with his insight into lovesickness cured his fear for lovesickness. The idea of medieval sexuality no longer haunted on Keats on his journey to love, but is criticized for its excessive rationality.

Introduction…………………………….1
Chapter I: Keats’s Awareness of Lovesickness
and Love Melancholy…………………11
Chapter II: Amatory Magic, Pharmakon, Demonic Temptress and Sick Lovers in Keats’s Poetry…41
Chapter III: The Restriction of Lovesickness and Keats’s Renouncement of It………...63
Conclusion………………………….....111
Works Cite……………………………...115

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