Dogs pick up on their owners’ feelings. If you are afraid of a person, your dog will express your fear for you by snarling. The other person might be perfectly decent, but something about them triggered your fear (maybe they smell like the teacher who bullied you, or they remind you of someone your parents hated…). The dog doesn’t care why; if you are afraid of this person, that’s good enough for him to declare them an enemy.
A very well balanced Comment below, on Dogs, Thank you.
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Who Watches the Watchers? 