My empirical studies into the neurobiology of consciousness have convinced me that many species share the sights and sounds of life with us humans. Why? First, except for size, there are no large-scale, dramatic differences between the brains of most mammals (including humans). Second, when people experience pain and distress, they contour their face, moan, cry, squirm, and try to avoid anything that would trigger a reoccurrence of the pain. Many animals do the same. Likewise for the physiological signals that attend pain–like changes in blood pressure, dilated pupils, sweating, and an increased heart rate. Because it is likely that mammals can consciously experience the pains and pleasure of life, we should not be eating their flesh.
It was difficult for me to follow this growing realization with action–the taste of meat is deeply ingrained! The death of my beloved companion Nosy a few years ago provided the final impulse to make me live in accordance with my belief. I am now an ovo-lacto vegetarian.
Koch, of course, is right. One of the great themes of post-Darwinian science is the inter-relatedness of life. From the perspective of our cells, there is little difference between a human and a chicken, or even a sea slug. All animals use the same neurons and the same neurotransmitters. Pain receptors in different species share a similar design. Blood and flesh and skin are always constructed of the same elemental stuff.
That said, I really like the taste of bacon.
But I also wonder about the corollary of this argument. Let’s say there was a species that used a totally different design for its neurons, and reacted to pain in a completely unique way. In other words, this species didn’t share our biological inheritance. Would it then be alright to eat them? I mean, at a certain point vegetarianism just has to be about not consuming living things, regardless of whether not they share our nociperception or sensory system.