Fortune versus Human Choice
Chaucer’s narrator regularly alludes to the concept of fortune, personified by the goddess Fortuna and her symbol of the wheel. While a man is held at the top of Fortuna’s wheel, he has good luck and experiences positive outcomes. Yet, he is always in danger of the wheel suddenly turning and encountering major challenges. At the beginning of the first book, it is warned that Troilus will move "from woe to joy, and then out of joy," confirming from the start that his fortune will fluctuate and end quite badly. The question of fortune is poised throughout Chaucer’s text: are the characters wholly controlled by fate or are they able to intervene through their own choices?
There are some decisions made within the romance that are clearly the product of free will: Troilus and Criseyde’s initial meeting at Deiphebus’ house, the exchange of letters, and the lovers' consummation. Yet, Fortune also seems to orchestrate some decisions throughout: Criseyde looks out her window just as Troilus is riding past and becomes smitten; she hears Antigone sing a love song in the garden just as she considers Troilus as a love interest; Troilus spots Criseyde’s brooch on Diomede's tunic, confirming her betrayal.
Fortune is not only a thematic concept in Chaucer’s romance, but also a structural one. The pattern of Troilus’ fortune is wheel-like, with him building himself up in the first two books, reaching his peak moment in the third, and falling for the remainder of the story.
Courtly Love
Love is central to Chaucer’s tale, and Troilus and Criseyde’s love affair follows many conventions of the medieval concept of "courtly love." This includes worship of the maiden from afar (Book 1), rejection of the male by the virtuous lady (Book 2), and chivalric behavior (Book 5). In Book 2, Troilus complains of a sickness that he cannot recover from, and he regularly faints. These are presented as symptoms of "lovesickness," a medieval idea that suggested to be deprived of one’s love was akin to a physical illness.
The maiden initially rejecting her suitor was also a characteristic element that is included in Chaucer's text. As the convention goes, the lady must first be seen as publicly demure, and reject the man's first advances before submitting to his desire. However, Chaucer's story differs slightly from other literary romances in that it doesn't comfort readers with a happy ending. Instead, Criseyde decides to betray Troilus for Diomede for the sake of comfort and security.
Troilus' insurmountable heartbreak is a rather dire conclusion to the drama, yet it is a conscious plot choice by the author, who uses his hero's downfall to impart a lesson to his readers about the true nature of love. For Chaucer, the silly conventions of courtship and infatuation are a mere shadow of a greater spiritual love which must first be directed towards God. All else, as demonstrated through Troilus' example, brings immense suffering and binds one ultimately to the illusion of "worldly vanity."
The Stars and the Gods
As previously stated, Fortune and human choice dictate much of the action in Troilus and Criseyde. Yet ancient astrology and mythology is also a very important structure in the worldview of the characters. Chaucer refers to the Ptomelaic structure of medieval astrology, which is based on eight spheres, with each sphere corresponding to a planet in the solar system. The placements of the planets at any moment have a direct effect on earthly events. At the beginning of each book, the narrator dedicates verses to a certain gods or goddesses whose influence is dominant in the characters' affairs. Chaucer often invokes astrological placements to explain plot points, such as when Criseyde first lays her eyes on Troilus. Her immediate attraction is rationalized as the workings of Venus, who represents love, being "wel’ arayed"—meaning that it is situated in the right place for a romance to blossom.
The gods, both as planets and as personified deities, rule the characters' lives, frequently mentioned and prayed to as purveyors of all human drama and destiny. Troilus especially sees the gods as pulling the strings of his life, whether it be the joy or the sorrow, attributing his downfall not to error or bad luck but the conscious tinkering of the celestial spheres.
However, by the end, Chaucer as the narrator brings the conclusion that the "pagan gods" of the Greek pantheon are not of a higher divine order, even suggesting that these gods are somewhat responsible in the vanity and downfall of his characters. The book finishes with his urging that the reader put his faith in God, who he equates with Christ. In this way, Chaucer brings a Christian message: that worshipping multiple deities is a form of idolatry and that there is only one true God.
Betrayal
The romance of Troilus and Criseyde ultimately ends in betrayal; a turn of events that may surprise the reader if it were not for the narrator’s frequent allusions to future events. Criseyde, going against her passionately spoken vows and promises of faithfulness, ends up staying on the Greek side and partnering up with a new lover. There are many clues that suggest Criseyde is dishonest with Troilus in her letters about her desire to return, and seemingly makes little effort to flee to Troy. Yet the betrayal here is not one-dimensional and it would be too easy to merely paint Criseyde as a villain who has acted wrongly. Rather, Chaucer shows us how Criseyde suffers and struggles deeply over her decision and feels legitimate remorse. In many ways, the maiden is put into a difficult situation, where she must either risk her reputation and even her life for Troilus, or settle for the security and comfort of a life with Diomede. Clearly, her passion is not as strong as that of Troilus, yet the reader is made to question whether it is right to hate Criseyde for her actions, as Troilus does. And there is a silver lining to it all; while the betrayal brings Troilus extreme suffering and eventual death, he also learns the value of spiritual love of God over worldly love, realizing that only a relationship with God can be a completely faithful and trustworthy one.
Dreams
There are two very important dreams that occur in the story, with both having prophetic connotations. The first dream is Criseyde’s: she dreams that a large white eagle swoops down to her and painlessly removes her heart from her chest and replaces it with its own. This is representative of the introduction of Troilus into her life, and the affair where they will commit their hearts to each other. The second dream is Troilus' and occurs after Criseyde has left for the Greek camp. In the dream, he witnesses a large boar embracing Criseyde. Troilus interprets the boar as a representation of Criseyde's new lover. After the boar dream, Pandarus tries to soothe Troilus by insisting that dreams are not as meaningful as he believes. This advice is proven to be ironically wrong when Troilus consults his sister Cassandra, who uses myth and history to show the significance of the dream as a definite symbol of betrayal.
Thus in the world of Troilus and Criseyde, dreams are more than random occurrences but serve as an important means for revelation. The willingness of the characters to fully embrace the symbolic meaning of their dreams either aids or hinders them; Troilus' initial denial of his dream's clear message, for instance, only creates more suffering for him in the long run.
Duality
Troilus and Criseyde deals with many extremes: love and hatred, life and death, war and peace. The character of Troilus demonstrates the intense ups and downs of someone ruled totally by their emotions, as he bounces from sorrow, to elation, and back to grief throughout the course of the story. This instability is mirrored in the external events, where there is clash between Greece and Troy, temporarily peace, and then eventually renewed conflict to an even more violent level.
It becomes obvious that such extreme duality can only result in a chaos that breeds destruction, whether it be of men or of cities. This is elaborated also in the persistent symbol of Fortune; her wheel may temporarily bring one up, but what goes up most come down, and often the fall is felt as a crushing blow to the soul. After Troilus dies and ascends to heaven, he comes to the realization that the conflicts of the world cause much suffering and finally he finds stability and peace in his love for God.
A Code Of Chivalry
A medieval chivalric code differs slightly from the modern definition of courtesy. Chivalry was a strict code for warriors that involved courage and ability on the battlefield, courtesy in love, and an absolute code of honor. While there are implications of the Trojan War, the romance is set almost wholly away from the battlefield. It therefore becomes difficult to judge Troilus on his chivalry as a warrior, as it is never witnessed firsthand. In his relationship, Troilus tries to follow conventions of courtly love, yet is not always perfectly honorable; he and Pandarus almost forcefully try to woo Criseyde initially, with Troilus even spying on the lady at one instance.
Yet, in Book 4, Troilus comes out as virtuous and chivalric in his ability to let go of Criseyde and resist the temptation to kidnap and elope with her. When Troilus discovers Criseyde's betrayal, he is also chivalrous in his defeat, allowing himself to fall down the wheel of fortune with sorrow but without much of a fight. This is evident in the way that he confronts Diomedes on the battlefield but does not slaughter him.
