However, the question arises whose rights are more important: people's or animals'? It is true that we allow animals to be used for various purposes and sometimes it is cruel but we do so in order to achieve human benefit. It seems that it is generally not wrong to raise animals because meat is an important source of protein and a rich ingredient of man's daily diet. It is also not wrong to experiment on animals as in this way medicine and science make progress. Moreover, lab animals have another important role to fulfil; they have saved many lives serving as 'guinea pigs' to test a vaccine or the effectiveness of a drug.