Blake was critical of the marriage laws of his day, and generally railed against traditional Christian notions of chastity as a virtue. At a time of tremendous strain in his marriage, in part due to Catherine's apparent inability to bear children, he directly advocated bringing a second wife into the house. His poetry suggests that external demands for marital fidelity reduce love to mere duty rather than authentic affection, and decries jealousy and egotism as a motive for marriage laws. Poems such as "Why should I be bound to thee, O my lovely Myrtle-tree?" and "Earth's Answer" seem to advocate multiple sexual partners. In his poem "London" he speaks of "the Marriage-Hearse" plagued by "the youthful Harlot's curse", the result alternately of false Prudence and/or Harlotry. "Visions of the Daughters of Albion" is widely (though not universally) read as a tribute to free love since the relationship between Bromion and Oothoon is held together only by laws and not by love. For Blake, law and love are opposed, and he castigates the "frozen marriage-bed". In "Visions", Blake writes: