and then andrew would look at little miss and a sensation of great joy and warmth would spread through his positronic brain-a sensation that he had come to identify as `` love '' -and he would have to remind himself , allover again , that he was nothing more than a cleverly designed structure of metal and plastic with an artificial platinum-iridium brain inside his chrome-steel skull , and he had no right to feel emotions , or to think paradoxical thoughts , or to do any other such complex and mysterious human thing .