3. There is within me (and with sadness I have watched it in others) a knot of cruelty borne by the stream of love, much as our blood sometimes bears the seed of our destruction, and at times I was mean to Doodle.
Explanation:
This is the statement that most foreshadows the fact that the narrator will feel regret for something that he has done to Doodle. In this excerpt, the narrator tells us that he believes there is some element of cruelty within him, and that at times, this cruelty was shown in his dealings with Doodle, as he could be mean to him. This suggest that the author will be cruel to Doodle later in the story.
Neither, a metaphor would be like "I'm so hungry that I could probably eat an elephant," while a simile would have 'like' or 'as' to describe something.
