Other moments in the novel stand out. Further comments about the "Laws of Humanics" remind readers that humans are governed in the same way robots are, though the laws, necessary to the development of psychohistory, are more difficult to discover. Daneel and Giskard, in their conversations with humans, often resemble nothing so much as traditional English butlers not an unlikely comparison, since both are considered to be perfect servants. The novel also contains some well-wrought Asimov contrasts: humans have intuitions robots have only reason; Aurorans are anti-Earth Earthmen are anti-robot. In addition, the Spacer longevity and susceptibility to disease, because of their existence sheltered from heat, cold, deprivation, and bacteria, reflect H. G. Wells's Martians, as if to comment that the Martians should have taken greater precautions against Earth's germs, such as the Spacers' nose plugs and gloves. At one point (when challenged by Vasilia), touchingly, Giskard is swayed to action by his feeling, like Baley's, for Daneel's humanity, and in an exchange reminiscent of that in "That Thou Art Mindful of Him," both concede humanity to the other.