When discussing animal rights, I often find myself battling with this preposterous notion of purpose: some "have it," some "do not." I have never been able to see the world through it's hierarchal pre-disposition, but I am left to question what "purpose" is and why it should ever play to determine the value of one's life.
So, how do we measure purpose and should someone naturally have a greater value because of who or what they are?
Interesting questions ...
Past inequalities would have had us believe that this were true. In days gone by, being Caucasian would have instantly warranted a greater respect and deserving of life within a Western society. Similarly, being a woman or identifying as LGBT would have stripped you from some of the most basic rights. Why? Because the lives of those individuals were seen as inferior to those who were "superior." Thankfully, we have moved beyond the aforementioned injustices (although, obviously, there are exceptions) but the rights of individuals outside our own species continue to be widely disregarded.