1. The double standard is based on an ungrounded prejudice and bias that caters to the interests of one specie against the members of other species, otherwise known as speciesism, which is simply the age-old us vs. them mentality wielded to depict those which you seek to exploit as unimportant.
2. Modern science recognises higher cognitive faculties in certain species of nonhuman animals, not unlike that of humans, and in some circumstances are superior to the mental abilities of humans.
3. The double standard is challenged by the sheer fact that we have a moral obligation to nonhuman animals to recognise them as sentient beings and treat them with equal consideration.

Conclusion:

The double standard in our treatment of humans and nonhuman animals is incredibly unjustified, nonetheless western wisdom is now being filled with concrete results of scientific and philosophical analysis that will continue to endorse equal considerablity for non-human animals in this post-Descartes era.

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