This chapter leaves the Canterbury Tales, and marriage, behind and turns to the presentation of love outside marriage in Troilus and Criseyde. C. S. Lewis's classic essay ‘What Chaucer Really Did to Il Filostrato’ described Troilus and Criseyde as an expression of the code of courtly love in narrative form. For Lewis, courtly love was a unified and codified ideology that applied to all medieval romances from the eleventh century to Malory, and many of Chaucer's changes to Il Filostrato were ‘corrections of errors which Boccaccio had committed against the code of courtly love’. But subsequent scholarship has problematised this view. First, scholars of the Robertsonian school read Troilus and Criseyde as a Catholic condemnation of the sinful and corrupting effects of courtly love, set in a Pagan era only to emphasise the heathen nature of idolising women rather than loving the Christian God. Second, the existence of a courtly love as a clearly codified ideology that remained constant throughout the medieval period has been challenged and largely abandoned. Nevertheless, Troilus and Criseyde has continued to be read in relation to late medieval courtly culture and discourses about love. For example, Green has drawn attention to the importance of a court culture of love for understanding Troilus and Criseyde. That Troilus and Criseyde ‘conduct their affair in accordance with the code of fashionable behaviour in vogue in Chaucer's day’ has been asserted by A. J. Minnis, and Barry Windeatt provides further support for such a view.