This article is from the Mastiffs Breed FAQ, by mmcbee@access.mountain.net (Mike McBee) with numerous contributions by others.
A properly socialized Mastiff (which SHOULD be the only kind
there is) will stand or sit beside you politely when a
stranger is around. The world is full of people who are
strangers to you and your dog, but who are nice, normal,
decent folks who pose no threat. A Mastiff that is properly
socialized (and free of severe shyness) should be polite,
possibly aloof, but eventually friendly, after the dog sees
your positive reaction to someone.
 
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