jeff144 wrote:One thought that keeps me from changing careers is that I would likely choose to benefit from medical research regardless of whether I was participating. Every new drug goes through animal testing and animals are always euthanized after testing. There is also much suffering that is imposed outside of merely killing animals. For example, inducing tumors in mice for cancer research.
In some ways, I suppose it parallels the concept of eating meat versus being a butcher. Why is it acceptable (in the eyes of some) to mindfully consume meat but not mindfully take an animal's life? I don't want to get sidetracked though since I know that there has been much discussion on meat eating.
I think that an animal (if it were capable of forming such thoughts) probably wouldn't care who, several links down the chain of command, is perhaps adding incentive to its destruction. The guilt lies in the hands of the being who decides, of his or her own free will, to hurt another living creature.
We are responsible for our own actions; if, by doing something, we create suffering, then it's not an appropriate action to take. If I kill an animal for my own sustenance, I am responsible directly for causing that animal to die. In the same way, if I go to a butcher or a seafood shop and pick an animal to be slaughtered for me, then I am directly responsible there as well. If not for my actions, that animal would not have suffered at that moment.
If I go to a restaurant where I order a steak, however, my biggest sin is offering a slight financial incentive for the restaurant to continue stocking meat; however, because a) the being is already dead and my refusal will not in any way bring it back to life, and b) because the meat is already there and will simply be eaten by someone else or thrown out should I refuse, I don't think it's reasonable at all to say that I have culpability in the destruction of the creature I am eating.
The rules the Buddha gave to monks in regard to meat are as follows:
Monks, I allow you fish and meat that are quite pure in three respects: if they are not seen, heard or suspected to have been killed on purpose for a monk. But, you should not knowingly make use of meat killed on purpose for you.
The only reason I'm digressing here is to point out two things. First, you shouldn't feel guilty or culpable in any way for the suffering animals have felt in order to bring you medicine or clothing because those industries have nothing to do with you and would continue just fine without you. You do not make those animals suffer by taking insulin or some other medicine; the people who inject the poison into the creatures themselves do.
Secondly, you can use the Buddha's prohibitions on meat as a guide for other things. It is definitely against the Buddha's teachings to intentionally kill or otherwise harm sentient beings for any reason. That is not up for debate. However, if you got a position as any kind of analyst or supervisor, you would be free from blame so long as the animals were not directly killed for you or so long as you did not direct others to kill them. I'm not sure on the specifics of your position as a biologist but perhaps this is possible?
Either way, the joy of renouncing violence and developing compassion is far greater than the joy of any paycheck. I know that sounds trite, but it really is true. I would urge you to commit yourself to living harmlessly and enjoying the gift of non-violence.
Sidenote: I don't think bacteria are considered sentient in traditional Buddhist thought, but as the existence of bacteria is a recent discovery, it's hard to say what the Buddha would have declared. I think the scientific evidence suggests that bacteria cannot know or experience in a direct way, so I doubt their destruction would be bad kamma.
Gain and loss, status and disgrace,
censure and praise, pleasure and pain:
these conditions among human beings are inconstant,
impermanent, subject to change.
Knowing this, the wise person, mindful,
ponders these changing conditions.
Desirable things don’t charm the mind,
undesirable ones bring no resistance.
His welcoming and rebelling are scattered,
gone to their end,
do not exist.
- Lokavipatti Sutta
Stuff I write about things.
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but if being a soldier can be Right Livelihood then so can many other occupations which cause death or suffering. I tend to take a pragmatic approach (maybe it comes from having grown up on a farm!) and simply try to minimise the harm I cause, and maximise the good I do, but without tying myself in knots over it. That, for me, covers 90% or more of the situations with 10% or less of the effort. 
