Taking his views from these writers, it was natural for the youthful Shelley to think and write chiefly of the evils arising from the law, which forbade a man to leave his wife and straightway attach himself to another woman. In constructing the note to _Queen Mab_, it was enough for him to put together, with no common smartness and one or two original touches, the remarks of previous writers on the troubles resulting from the permanence of matrimonial obligations. Contemning marriage from his boyhood, after the fashion of his teachers, he was eloquent about the difficulty of escaping from it. Apart from a statement of the grand principle that ‘love was free,’ and that every person should be at liberty to marry whomsoever he pleased, he does not seem to have troubled himself about the divers impediments to the first entrance into the unendurable bondage, before he went to Geneva. It was otherwise on his return from the residence in Switzerland with Byron. The startling discovery, that they were believed to be living in incestuous intimacy with the same two women, caused each of the poets to ponder the nature of the crime with which rumour charged them. Stirring and fascinating Byron’s imagination, the scandal bore fruit in _Manfred_ and _Cain_. Stimulating and holding Shelley’s fancy, it resulted in _Laon and Cythna_. It is interesting to observe how differently the two poets dealt with the same repulsive subject. For the timid sceptic and half-hearted innovator, who to the last was (as Shelley put the case to his wife at Pisa) ‘little better than a Christian,’ it was enough to point to the crime in _Manfred_, as one of the hideous possibilities of vicious desire,--as a monstrous and appalling extravagance of wickedness, too hideous to be spoken of precisely; as an offence so loathsome and revolting, that poetry could refer to it only by vague hints and obscure suggestions. In _Cain_ he could refer with cynical mockery to times when, if _Genesis_ were true, brothers necessarily mated with their sisters, for the accomplishment of the Creator’s purpose;--mockery, that was not so much a palliation of the iniquity, as an assault on the credibility of the Book which seemed to sanction the wickedness.