Here is my attempt to convince you also of 1 (in your numbering):
I disagree with your: "From a preference utilitarian Perspective, only a self-conscious being can have preferences for the future, therefore you can only violate the preferences of a self-conscious being by killing it."
To the contrary, every agent which follows an optimization goal exhibits some preference (even if itself does not understand them). Namely that its optimization goal shall be reached. The ability to understand ones own optimization goal is not necessary for a preference to be morally relevant, otherwise babies and even unconscious people would not have moral weight. (And even non-sleeping people don't understand all their optimization goals.)
This leaves the problem of how to weight various agents. A solution which gives equal weight "per agent" has ugly consequences (because we should all immediately take immunosuppressants to save the bacteria) and is ill-defined, because many systems allow multiple ways to count "agents" (each cell has equal weight? each organ? each human? each family? each company? each species? each gene allele?).
A decent solution seems to be to take computing power (alternatively: the ability to reach the optimization goals) of the system exhibiting optimizing behavior as a "weight" (If only for game-theoretic reasions; it certainly makes sense to value preferences of extremly powerful optimizers strongly). Unfortunately, there is no clear scale of "computing power" one can calculate with. Extrapolating from intuition gives us a trivial weight for bacterias' goals and a weight near our own for the goals of other humans. In the concrete context of killing animals to obtain meat, it should be observed that animals are generally rather capable of reaching their goals in the wild (e.g. getting food, spawning offspring) - better than human children, I'd say.
I have grown up in a family of meat-eaters and therefore have been eating meat all my life. I until recently I have never spent much time thinking about it. I justified my behaviour by saying that animal lives do not matter, because they are not self-conscious and animal pain does not matter, because they have no memory of pain and therefore, as soon as the actual pain is over it is like it has never happened.
In the recent weeks I have spent some time to properly think this through and form an informed believe about whether I can justify eating meat. I would like to hear your thoughts about my thought process and results, because this is a decision that I really don’t want to get wrong.
I have Identified 5 possible problems with meat consumption.
I have decided to ignore problems 4-5 at the beginning, because admitting that they are true would impose weaker restrictions on me. If I come to the conclusion, that I don’t want to eat meat for reason 1, I could no longer eat any meat and reason 2 would forbid me to eat factory farmed meat, which would essentially bring my meat consumption down to something close to zero.
Reasons 4 and 5 would limit my meat consumption far less, since I do lots of other things that are unhealthy (like eating candy and snacks) or harmful to the environment (like traveling by plane) and while I might come to the conclusion that I want to reduce my meat consumption for reasons 4-5, I expect to have many situations left, where eating meat gives me enough utility to still do it in spite of that reasons.
Reason 3 would also be important, but I am fairly sure, that the problem mostly lies with the lack of spending power in poorer countries, and that it will not lead to more food in Africa if I stop eating meat. For that reason I did not do further research on this.
So what I did was to think about problems 1 and 2 and decide to revisit 4 and 5 if I come to the conclusion that 1 and 2 still allow me to continue eating meat like I do now.
Is it justifiable to kill animals?
It is clear to me that it is wrong to kill a Human being with a not significantly damaged brain. It is also clear that I have absolutely no problems with killing bacteria or other very simple living beings. Therefore there must exist some features besides the fact that they live that a human has and a bacterium has not, that divides living beings into things that I am willing to kill and things that I am not willing to kill.
The criterion that I used up to know was self-consciousness, which is very convenient because it puts the line between humans (and likely great apes as well) on one side, and basically everything I want to eat on the other side.
There are quite a few things that justify this criterion such as:
There are however other Arguments against it.
I find the arguments against killing animals to be far weaker, since I do not follow the particular form of utilitarism that supports them and since I cannot really explain why the features I named under 1 should forbid me to kill animals. In addition to that I count the fact that Peter Singer, who is against all killing of animals and is arguably a pretty clever person has found no better way to justify his statement, that one should not kill animals at all, than the idea that this will lead us to continue to objectify them and ignore their pain. Since Singer has found no better reason and he probably spent a lot of time doing it, it is likely that there is none.
Although I am fairly confident, that killing Animals is in line with my ethical believes I still see some trouble. If I am wrong on this this might be an incredible harmful decision, since it will lead to the death of many animals (probably hundreds of them, if I don’t reduce my meat consumption for other reasons). Therefore I have to be incredibly confident that I have not overlooked something in order to continue to eat meat. And I have limited time and probably a strong motivation to come to the conclusion that meat eating is okay, which clouds my judgement. I feel that I need more evidence. As far as I know there are lots of meat eaters here and some of them will have thought about this. Why are you so confident that animal life’s do not matter? Is it that I overlooked major arguments or is the self-consciousness just a more of a knock down argument than I think?
Animals and Pain
It is relatively well established that animals show reactions that one could associate with pain and they have a nerve system that allows pain. Singer has proclaimed that in his 1975 book Animal Liberation for mammals and birds and cited research on it, and as far as I know no one has really corrected him on that. I also found papers that claim the same for fish and lobsters and I have not found any counterevidence. So the question that remains is, do animals get negative utility from pain, and do they have utility functions at all.
Eliezer Argues in this post https://m.facebook.com/yudkowsky/posts/10152588738904228 that they don’t have utility. I can understand his model, but I could also imagine that an animal mind works in other ways. I am no expert in evolutionary biology, but as far as I know, the mainstream opinion among scientists right now is that animals have pain.
There is for Example the Cambridge declaration of conciousness (http://fcmconference.org/img/CambridgeDeclarationOnConsciousness.pdf). It might have a different understanding of the word consciousness compared to the one which I think is most popular among the lesswrong community (Consciousness as being aware of its own existence), but it clearly states that animals have affective states and therefor utility. If animals can suffer pain, than factory farming is incredibly wrong. I would therefore have to be very certain (surely above 99% confidence) of the fact that they don’t or I cannot justify to eat factory farmed meat. The question is: How can I be so sure if a significant amount of experts are of a different opinion. Does anyone have any actual research on the topic that explains the reasons why animals do not have utility in more detail than Eliezer did? Basically I would need something that not only explains why this is a plausible hypothesis but something that explain why they could not possibly have evolved in a way that they feel pain. So basically, why a pig that feels pain makes no sense from an evolutionary perspective.
If my current believes don’t shift anymore I will stop eating factory farmed meat, but not stop to eat any meat at all. I would be happy about any additional evidence, or about oppinions on the conclusions I draw from my evidence.