Cassius wanted to delay killing Caesar due to the warnings some soothsayers have given to Caesar.He does not know whether Caesar will come to the Capitol or not because of those warnings.He thinks Caesar is too superstitious and might well want to stay at home the day the conspirators have arranged to stab him.
Answer:Why doesn't proctor go to Salem to report what Abigail has told him? He is afraid that if he reveals Abigail to be a fraud, she will confess their affair.