Alright. So, I cannot claim to have read this entire thread, because that would be a lie...I'm lazy and too many of the arguments were becoming mind-numbingly petty.
The nutritional side of things has been resolved (for quite a while), and there appears to be no argument (rational/sensible argument, anyway) that being a vegetarian/vegan is at all unhealthy. In fact, several arguments have been made that claim vegetarianism is healthier than carnivorous actions ... There are indeed studies that back this up; one notable page I found is
here. So it does appear as though being a vegetarian is conducive to living.
Noted British professor John Webster has also published work describing the intelligence (and thus, ability to suffer) of cattle, see
this article. And it certainly seems that cattle do feel pain; if one pokes a cow or bull with an electric prod, they respond in much the same way as humans (vocalizing, movement away from the source of pain). It can thus be concluded that, based purely on external evidence (which is all we have direct access to), cattle suffer in the same way as humans.
Now, to clarify, we have to define what suffering is. There seems (at first glance on the Internet, anyway) to be two broad categories of suffering: the physical and the mental. The physical side of suffering is indeed quite expansive, covering everything from basic physical pain to itches or twitches. The psychological side of suffering is a bit more difficult to discern. A definition from
Merriam-Webster is "mental distress".
According to some in this thread, cattle do not experience psychological suffering (I'm taking it for granted that everyone accepts the experience of physical pain by cattle). One of the more common arguments I spotted was that cattle do not have consciousness.
This article, although short, addresses the issue and seems to conclude that animals have at least a simple form of consciousness.
In my opinion, it's impossible to prove (or disprove) consciousness in animals, for the simple reason that we are not them. The same problem arises when trying to discern consciousness in other humans. To me, other humans certainly seem to exhibit forms of consciousness (based on the fact that they respond similar to myself when encountering external stimuli). For example, upon greeting an individual, I say "hello" (or a similar salutation). If they respond in a similar fashion (saying "hello" back, for example), I tend to immediately assume they have some form of consciousness and proceed with conversation. However, computers are now capable of the same actions. Right now, it's impossible for me to determine whether anybody I meet has consciousness. I am the only human example of consciousness for me, and the same is true of everyone.
Back to my point. If we presume that a sample human possesses consciousness (and thus is capable of psychological suffering ... this is assuming that the former is both necessary and sufficient for the latter) based only on their responses to external stimuli, why should we not presume the same for cattle? Their lack of a response in English (or whatever your native language is) is no excuse, as they have no formal education in our languages. A human squirms, yells, runs away, responds with similar violence, etc. when confronted with pain (physical pain, that is ... similar but not identical responses ensue with psychological pain; my point remains regardless). If cattle do the same, we must therefore assume their possession of consciousness of at least vaguely similar type to humans, if we are to be "fair" to both parties.
But for me, because I cannot prove (or disprove) the existence of consciousness beyond my own, the assertion that cattle suffer is essentially moot. As is the argument that humans suffer. I prefer to err on the side of caution, and
not eat humans in case they
do have a consciousness. Also, the social and judicial consequences for eating humans is considerably less than that for eating cattle.
I keep red meat to a minimum, and fish are rarely on my plate as well. One of my favourite dishes is cheese tortellini with sun-dried tomato sauce. But meat does taste good (if properly prepared), and until society punishes me for eating it, I will continue to indulge on the rare occasion.
Overall, I agree with the vegans/vegetarians, but for different reasons. However, the spirit is willing, the flesh is weak.