Good Men

There are a number of situations in which N. attempts to define a certain group of people by one term. One example of this is his concept of "good men". What truly makes a good man? How is one person able to label an entire group and yet not be able to define what makes this person "good" or "bad"? This is a certain topic that doesn't seem to make sense to me because I do not think that N. is the man that should be appointed to label an entire group of people.