Its the size not the dog

Pit bulls are big muscular dogs, they leave big marks if they bite. There is a Yorkie that lives in my neighborhood. He bites each time anyone pets him. He is aggressive but he is small, he doesn't kill people but he bites everyone. Everyone in the neighborhood knows to be cautious but the owner still doesn't support muzzles. We don't mind but if it were to be a Pit bull we would think differently. Most small dogs are aggressive but we know that they won't do much harm. This is why most people are afraid of pit bulls. Their heads are the same size as ours.    
                                     
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