I have some grasp of human psychology, and have been known to predict the behavior of people with a certain degree of precision, but canine psychology is a lot more difficult. To what extent does human speech facilitate emotional interaction between man and dog? that's question number one. If words are in fact of no use whatsoever, then neither party has any choice but to read the other's gestures and expressions. Tail movement, for example, is crucial. But if you observe closely, you'll find that these movements of the tail are extremely complex and by no means easy to interpret.

*Dazai Osamu, "Canis familiaris" from Self Portraits*