The most callous, stupid things were done just because regulations required them...It was not until 1983, for example, that U.S. federal agencies stated that substances known to be caustic irritants such as lye, ammonia, and oven cleaners, did not need to be tested on the eyes of conscious rabbits.

As we realize that more and more things have global impact, I think we're going to get people increasingly wanting to get away from a purely national interest.

When fish experience something that would cause other animals physical pain, they behave in ways suggestive of pain, and the change in behaviour may last several hours.

As for cages themselves, an ordinary citizen who kept dogs in similar conditions for their entire lives would risk prosecution for cruelty. A pig producer who keeps an animal of comparable intelligence in this manner, however, is more likely to be rewarded with a tax concession or, in some countries, a direct government subsidy.

If you go back in time you'll find tribes that were essentially only concerned with their own tribal members. If you were a member of another tribe, you could be killed with impunity.

I do not believe that it could never be justifiable to experiment on a brain-damaged human.

The statement "I am in pain" may be one piece of evidence for the conclusion that the speaker is in pain, but it is not the only possible evidence, and since people sometimes tell lies, not even the best possible evidence. Even if there were stronger grounds for refusing to attribute pain to those who do not have language, the consequences of this refusal might lead us to reject the conclusion. Human infants and young children are unable to use language. Are we to deny that a year-old child can suffer?