Oryx and Crake

Snowman often thinks of phrases and seemingly random words that he half-remembers. What psychological reasoning might account for this? Why does Snowman keep thinking of and uttering these fragments? 

As Snowman looks back on his time with Crake, he realizes that there were clues about Crake’s worldview and plans that he did not notice this at the time. Can you think of any interactions, dialogue, or events that may be read as warning signs?

How do you perceive Crake throughout this novel? Does he have any altruistic, honorable aims (as he claims) or is he merely a power-crazed villain?