Personism is an ethical philosophy of personhood as typified by the thought of the preference utilitarian philosopher Peter Singer. It amounts to a branch of secular humanism with an emphasis on certain rights-criteria. Personists believe that rights are conferred to the extent that a creature is a person. Michael Tooley provides the relevant definition of a person, saying it is a creature that is "capable of desiring to continue as a subject of experience and other mental states". A worldview like secular humanism is personism when the empathy and values are extended to the extent that the creature is a person (apes get very similar rights, insects get vastly fewer rights, etc.).