Generally speaking, the IQ of a dog is equivalent to that of a six- or seven-year-old human child. The smartest among dogs is the Border Collie. Its intelligence can sometimes even be described as cunning. For example, some Border Collies will attack their owners when they are nearby. It shows that it takes great care of its little master, but when the master leaves, it may steal food from the little master's plate, and when the master comes back, it will pretend that nothing happened.