We strive to be perfect. We don't reach that, nor does anyone else.
Right now, animals are generally considered property. Animals do not have rights in the sense that humans have rights.
The ability to feel pain must be a consideration.
We will not just stand by and let things happen.
As long as there's anything we don't know about how a body works.
(The researchers) have to be able to justify the use of animals. It's extremely competitive.