Elementary Concepts of Objects and Classes — Question 4

It means that there can be different abstractions of an entity depending on the viewpoint of the user. Lets take the example of a pet dog. From the viewpoint of the dog's owner, the things that are essential for the dog are his favorite food, the colour of his food bowl, his favorite game that he enjoys playing with his owner, his preferred time for walk, etc. From the viewpoint of the dog's vet (doctor for animals), the important things about the dog are whether the dog's body functions are normal or not to ensure that the dog is healthy. Like this, there can be two abstractions for the dog — one for the dog's owner and the other for the dog's vet.