Just to give you a clue, most arguments are lost as soon as the person uses movie plots as proof.
In your opinion...
It works very well for me when speaking to americans of this particular culture. It is something people can relate to.
But for you I'll be more direct. I can program a robot or "virtual" character in a video game to "feel" pain to the point of making people cry. That is because they have a point of referenc with which to "interpret" the apparent "feelings" of the program.
The trap most are falling into on this thread is using their human brain and even their own life experiences "lens on life" as their point of reference to interpret the actions and reactions of animals.
Sometimes this doesn't even work when interpreting the actions and reacions of other people!