In Chapter 1 the reader is introduced to David Strorm, a 10 year-old boy who is a little different from society. David lives in the future, in a time after Tribulation. His society is determined to keep itself true to the Definition of Man.
The Definition of Man is a written, religious decree that describes the physical form of a human being. Any creature that has even a slight deviation from this definition is hateful in the sight of God and will be banished from their society.
In Chapter 1, the reader is also introduced to Sophie Wender. Sophie is a litte girl, around David's age, who has a mutation. Each foot of hers has six toes. David was approached by Sophie while playing on a bank. They played together and in the course of their adventure, Sophie's foot becomes wedged in a cleft in the ground. This leads to David's eventual discovery of her sixth toe (David assumes that there is another sixth toe on her other foot as well). David helps Sophie home, so that her mother could tend to Sophie's foot.
Sophie's mother, although quite aware of what David could do with his knowledge about Sophie, treats him well. David likes Mrs. Wender, for she does not give him the feeling that he is the one regrettable and unreliable factor in an otherwise orderly life, the way most people do at his home. The reader is lead to assume that David doesn't quite fit in at home.
Mrs. Wender feeds David, then makes him promise that he will never reveal what he has learned about Sophie. David is puzzled by the importance of doing so, but he promises just the same. David is just happy that he has made a friend and asks to see Sophie again. Mrs. Wender agrees as long as he can come without anybody finding out.
On his way back home, David begins to question the Definition of Man. It seems to him to be silly that Sophie, a normal girl, could be considered a blasphemy. He then decides that there is nothing really wrong with Sophie and that the ways of the world are puzzling.
This chapter gives us a subtle glimpse into a talent of David's. He seems to be able to pick up on other people's thoughts and feelings. Another thing that is mentioned is that he dreams of what must have been the civilization of the Old People. Both of these things are a foreshadow of what is to come in the novel.