How we cite our quotes: (Section.Paragraph) or (Section.Subsection.Paragraph)
Quote #4
At the outset, if a person in custody is to be subjected to interrogation, he must first be informed in clear and unequivocal terms that he has the right to remain silent. For those unaware of the privilege, the warning is needed simply to make them aware of it […]. It is not just the subnormal or woefully ignorant who succumb to an interrogator's imprecations […] (Opinion.III.3)
"Imprecation" means cursing or insult. Warren's saying that everyone can be vulnerable to being beaten down by that kind of treatment. You don't have to be an idiot to be a little unclear about your rights in those circumstances.
Quote #5
Crime is contagious. If the Government becomes a lawbreaker, it breeds contempt for law; it invites every man to become a law unto himself; it invites anarchy. (Opinion.IV.2)
The Court thinks it's a recipe for chaos if people see the government as operating outside the law. What's the point of being a good citizen if you can't count on the police to treat you fairly? If your mom didn't stop at red lights, would she have any credibility when she told you not to do it?