Peter Singer, an Australian philosopher born in 1946, may be the most controversial philosopher alive today. Many praise him for having fathered the" animal liberation" movement (his book of that title sold 400,000 copies and led to improved treatment of animals) and for promoting famine relief (for which he donates a fifth of his income). Others attack him as an evil neo-Nazi who rejects the sanctity of human life and has a permissive attitude toward killing handicapped infants. In this reading, Singer contends that racism and sexism are wrong because they give greater weight to the interests of those of one's own race or sex. Similarly, he claims," speciesism" is wrong because it gives greater weight to the interests of those of one's own species. The only non-arbitrary approach is to consider equally the interests of any sentient being-and thus to give an animal's suffering the same weight as an equal suffering of a human.