Anchor: It is only in old age that change is unwelcome, said the Astronomer, "and races can be old as well as individuals."  
Entailed: Change is only unwelcome in old age.
Contradiction: Old age makes people wish for change.
Contradiction: Porto Santo is one of many inhabited archipelago islands.
Contradiction: The boys are playing.
Contradiction: Bill Moyers and George Lucas have never spoken.
Contradiction: You have to take whatever you can get.