muggles and knowing about magic

[DinaYS at aol.com]

No: HPFGUIDX 23184

As an aside to the question about how a muggle born witch or wizard 
rsvps to Hogwarts acceptance and gets to diagon alley,  there are 
obviously muggles who know about magic (ie  Hermione's parents, 
Dursleys)  what is it that keeps them from giving away the secret, 
plus, what other muggles know (ie government, clergy)  Just a thought.
Dina