Without any grip of the notion of a rule and an exception, the general idea of judging people's heredity breaks down and is useless. For this reason: that if everything is the result of a doubtful heredity, the judgment itself is the result of a doubtful heredity also. Let it judge not that it be not judged. Eugenists, strange to say, have fathers and mothers like other people; and our opinion about their fathers and mothers is worth exactly as much as their opinions about ours. None of the parents were lunatics, and the rest is mere likes and dislikes. Suppose Dr. Saleeby had gone up to Byron and said, "My lord, I perceive you have a club-foot and inordinate passions: such are the hereditary results of a profligate soldier marrying a hot-tempered woman." The poet might logically reply (with characteristic lucidity and impropriety), "Sir, I perceive you have a confused mind and an unphilosophic theory about other people's love affairs. Such are the hereditary delusions bred by a Syrian doctor marrying a Quaker lady from York." Suppose Dr. Karl Pearson had said to Shelley, "From what I see of your temperament, you are running great risks in forming a connection with the daughter of a fanatic and eccentric like Godwin." Shelley would be employing the strict rationalism of the older and stronger free thinkers, if he answered, "From what I observe of your mind, you are rushing on destruction in marrying the great-niece of an old corpse of a courtier and dilettante like Samuel Rogers." It is only opinion for opinion. Nobody can pretend that either Mary Godwin or Samuel Rogers was mad; and the general view a man may hold about the healthiness of inheriting their blood or type is simply the same sort of general view by which men do marry for love or liking. There is no reason to suppose that Dr. Karl Pearson is any better judge of a bridegroom than the bridegroom is of a bride.