Do most dogs treat people based on their physical apparence?

Do most dogs treat people based on their physical appearance?
Not always. Most dogs I think, if well socialized, think all people should fall in love with their grand self. However if a dog has been abused anyone that reminds them of that person will be on their "suspect" list. Some one not to be trusted. If someone has just scared the crap out of them anyone reminding them of that person is to be feared. It could be a persons size & shape. It could be a beard or mustache. It could be someone using a cane. On the other side of that coin if a dog is reminded of someone they love they will want to get to that person.