If penicillin had been judged by its toxicity to guinea pigs, it might never have been used by man.

Killing a defective infant is not morally equivalent to killing a person. Sometimes it is not wrong at all.

If they [animals] were really to get the equal consideration that I believe they should, we wouldn't have commercial animal production in this country.

It is a mistake to assume that the law should always enforce morality.

To be a utilitarian means that you judge actions as right or wrong in accordance with whether they have good consequences. So you try to do what will have the best consequences for all of those affected.

Every profession will have its rogues, of course, no matter what oaths are sworn, but many health care professionals have a real commitment to serving the best interests of their clients.

If a being suffers there can be no moral justification for refusing to take that suffering into consideration. No matter what the nature of the being, the principle of equality requires that its suffering be counted equally with the like suffering - insofar as rough comparisons can be made - of any other being. So the limit of sentience is the only defensible boundary of concern for the interests of others. To mark this boundary by some other characteristic like intelligence or rationality would be to mark it in an arbitrary manner. Why not choose some other characteristic, like skin color?